Improving the Retention Rate of Fat Grafting by Botulinum Toxin A: A Randomized, Self-controlled, Clinical Trial.

BACKGROUND: Botulinum toxin A (BTX-A) can enhance the efficacy of fat grafting. However, most studies conducted animal experiments, lacked objective clinical data, or were non-randomized controlled trials. Thus, objective evaluation of the clinical effectiveness of BTX-A is still elusive. METHODS: A randomized, self-controlled trial (2020-2022) on 16 patients who underwent bilateral autogenous fat breast augmentation was performed with each patient receiving autologous fat graft and BTX-A on one side and fat graft and equal volume of saline on the other side. All patients were followed. The effects of BTX-A were evaluated objectively by comparing the remaining bilateral fat graft volumes obtained through digital three-dimensional reconstruction. The improvement of each breast appearance and complication were assessed by the physician and patients who were blinded to the treatment. RESULTS: The outcome of fat breast augmentation was evident for both sides at follow-up with no evidence of fat embolism, vascular/nervous injury, infection, and prolonged bruising. The analysis of the three-dimensional reconstruction data and assessments from both physicians and patients showed significant differences in the fat graft retention volume between the BTX-A side and the control side. No significant difference was found in the incidence of complications between the two sides. CONCLUSIONS: Autogenous fat breast augmentation is safe and effective. This study shows that BTX-A can significantly improve the retention rate of fat transplantation, but cannot reduce complications. Trial registration This study was registered prior to patient enrollment (ClinicalTrials.gov identifier:ChiCTR2100054878). LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Timing of Laser Intervention on Facial Scars: A 3D Imaging and Scar Scale Analysis in a Retrospective Study.

OBJECTIVES: Scars resulting from injuries or surgical procedures often present both physical and aesthetic challenges. Recent studies have indicated promising results in improving postoperative scar outcomes through the combined use of specific laser technologies. Nevertheless, there remains a crucial need for further exploration to ascertain the optimal timing for initiating such treatments. METHODS: In this retrospective investigation, a cohort of 47 adult patients who did not require hospitalization was analyzed. These patients were divided into two distinct groups: Group A, which received intervention beginning 2 weeks after their respective operations, and Group B, which commenced intervention 4 weeks postoperation. Each group underwent a comprehensive treatment protocol consisting of five laser sessions. Initially, patients underwent three sessions of V-beam pulsed-dye laser (PDL) therapy followed by two sessions of ablative fractional CO2 laser (AFL) therapy. Evaluation of outcomes was conducted using advanced imaging techniques such as Antera 3D imaging, in conjunction with established scar assessment tools including the Vancouver Scar Scale (VSS) and the University of North Carolina "4P" Scar Scale (UNC4P). RESULTS: All patients successfully completed the full course of five treatment sessions, with no dropouts and no reported adverse events. Baseline cosmetic assessments of scars were equivalent across both groups. In Group A, the mean VSS scores decreased from 7.04 before treatment to 5.29 at 3 months posttreatment and further to 4.33 at 6 months posttreatment. Meanwhile, in Group B, scores decreased from 7.52 to 6.83 at 3 months and 6.17 at 6 months. There were no statistically significant differences in baseline VSS scores between the two groups (p = 0.34). At both the 3- and 6-month follow-up points, mean VSS scores were significantly lower in Group A compared to Group B (p < 0.05). Similar trends were observed in UNC4P scores. Statistically significant differences were noted across all time points (baseline, 3 months, and 6 months posttreatment) for both VSS and UNC4P scores (p < 0.05). Subset analysis revealed greater improvements in texture and depression volume at 3 months posttreatment, while improvements in depression area, depth, elevation variation, and area were more pronounced at the 6-month mark. CONCLUSIONS: Early intervention using the combined 595-nm pulse dye laser and CO2 ablative fractional laser (AFL) 2- and 4-weeks post-surgery proves to be an effective and safe method for improving scar outcomes, particularly for facial surgical scars when treatment starts 2 weeks after surgery. However, further research is needed to refine our understanding and address potential study limitations.

Liposuction Through an Axillary Fold Incision Combined with a Small Areola Incision to Treat Gynecomastia.

BACKGROUND: Gynecomastia is a progressive disease characterized by enlarged breasts, affecting a significant proportion of men. Persistent gynecomastia negatively affects the psychological and emotional development of patients; therefore, surgical intervention is required. In this article, we describe a surgical technique, where liposuction through an axillary incision is used in combination with a single small periareolar incision, to obtain the most minimal scars in the treatment of gynecomastia. METHODS: Between June 2021 and June 2023, 125 patients with different Simon grades of gynecomastia were enrolled. The patients' basic conditions and operation processes were recorded. Following surgery, a score was assigned according to the five main aesthetic aspects of the surgical procedure. RESULTS: In total, 125 patients with gynecomastia were treated with a pre-axillary fold incision combined with a small areolar incision. There were 17 cases of Simon grade I, 46 grade IIA, 42 grade IIB, and 20 grade III. The average operation time was 45.8 min, the average liposuction volume was 250.5 mL, the average glandular tissue volume was 50.5 g, intraoperative blood loss ranged from 15 to 60 mL, and the average hospital stay was 3.2 days. Regarding the postoperative aesthetic effect, doctors scored > 4 points, and the patient satisfaction score was > 7.5, which fully affirmed the aesthetic effect of this method. CONCLUSIONS: Treatment of gynecomastia through an anterior axillary fold incision combined with a small areolar incision is safe and feasible, involving a simple procedure, short operation time, and few complications. Its efficacy and cosmetic effects could lead to its use as a primary surgical method to treat gynecomastia. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .

Vertical Scar Reduction Mammaplasty Using the Superomedial-Based Pedicle Technique in Gigantomastia.

BACKGROUND: Breast reduction surgery has witnessed significant advancements in recent years; however, it continues to pose challenges for both surgeons and patients when dealing with cases involving excessive breast volume and severe breast ptosis. This study aimed to assess the aesthetic outcomes and the impact on the quality of life, as measured by the BREAST-Q questionnaire, in patients with gigantomastia and severe breast ptosis who underwent reduction mammaplasty using the superomedial-based pedicle technique. METHODS: We present a retrospective series comprising 84 patients who underwent reduction mammoplasty utilizing the superomedial pedicle technique. The surgical resections exceeded 1 kg per breast, with a mean resection weight of 1506.58 g (right breast) and 1500.32 g (left breast). The preoperative mean suprasternal notch to nipple distance measured 40.50 cm (right breast) and 40.38 cm (left breast). Postoperatively, the patients were followed up for a minimum of 6 months. Both preoperative and postoperative BREAST-Q surveys were administered to the participants, and scores were analyzed using descriptive statistics. RESULTS: Complications were observed in 3 patients (3.57%), characterized by partial loss of the areola, which resolved spontaneously over time. Additionally, 2 cases of hematoma and 2 instances of minor delayed wound healing were reported. All patients expressed satisfaction with their aesthetic outcomes, as they achieved a natural breast shape and minimal scarring, along with symptomatic relief. CONCLUSIONS: The superomedial pedicle reduction mammaplasty technique has demonstrated its ability to produce satisfactory aesthetic outcomes and long-term benefits in patients with excessively large breasts. Careful patient selection and postoperative management are vital for achieving optimal results. Further investigations involving larger sample sizes and longer follow-up periods are warranted to validate our findings. LEVEL OF EVIDENCE: IV.

Copper-Catalyzed Enantioconvergent Radical N-Alkylation of Diverse (Hetero)aromatic Amines.

The 3d transition metal-catalyzed enantioconvergent radical cross-coupling provides a powerful tool for chiral molecule synthesis. In the classic mechanism, the bond formation relies on the interaction between nucleophile-sequestered metal complexes and radicals, limiting the nucleophile scope to sterically uncongested ones. The coupling of sterically congested nucleophiles poses a significant challenge due to difficulties in transmetalation, restricting the reaction generality. Here, we describe a probable outer-sphere nucleophilic attack mechanism that circumvents the challenging transmetalation associated with sterically congested nucleophiles. This strategy enables a general copper-catalyzed enantioconvergent radical N-alkylation of aromatic amines with secondary/tertiary alkyl halides and exhibits catalyst-controlled stereoselectivity. It accommodates diverse aromatic amines, especially bulky secondary and primary ones to deliver value-added chiral amines (>110 examples). It is expected to inspire the coupling of more nucleophiles, particularly challenging sterically congested ones, and accelerate reaction generality.

Modified Internal Pudendal Artery Perforator Flap Interposition for Rectovaginal Fistula.

IMPORTANCE: Rectovaginal fistula (RVF) is a challenging condition associated with recurrences and significant functional impairment. OBJECTIVES: The internal pudendal artery perforator (IPAP) flap has become a viable option for reconstructing the vagina and perineal regions. This study aims to introduce a modified technique of IPAP flap interposition and evaluate its postoperative outcomes in the treatment of low RVF. STUDY DESIGN: Sixteen patients with RVF who underwent modified IPAP flap interposition between 2016 and 2021 were retrospectively enrolled. Recurrence rate, the satisfaction of vulvar appearance (Visual Analog Scale), and quality of sexual life (Female Sexual Function Index score) were followed up and analyzed. RESULTS: All patients presented with low fistula with a mean diameter of 8.3 mm. The mean width and length of the IPAP flaps were 3.8 and 6.2 cm, respectively. The mean follow-up period was 14.1 months. All patients achieved successful healing without recurrence. High satisfaction was reported for the cosmetic effect of the vulva with a mean Visual Analog Scale score of 8.4. The proportion of female sexual disorder exhibited a statistically significant reduction, decreasing from 100% preoperatively to 38% after surgery ( P < 0.05). CONCLUSIONS: The modified IPAP flap interposition is a reliable and safe option for repairing low RVF, with high success rates and minimal donor site morbidity. Moreover, this procedure provides a suitable volume flap and preserves the vaginal physiological environment, which benefits postoperative sexual function.

Clinical Application of Long-Pulsed 800-Nm Diode Laser Depilation Technology on Microtia Reconstruction in 965 Patients.

BACKGROUND: The issue of hair growth on reconstructed ears has been a matter of concern for both patients and surgeons, despite the notable progress made in microtia reconstruction technology in recent times. OBJECTIVE: This study aims to present the practical implementation of long-pulsed 800-nm diode laser depilation technology in the field of auricular reconstruction. Furthermore, it seeks to establish a comprehensive and standardized protocol for utilizing lasers in the reconstruction of microtia ears. METHODS: A total of 965 patients (comprising 1021 ears) diagnosed with congenital microtia underwent treatment using 800-nm long-pulsed diode laser depilation. The participants received 1-3 treatment sessions with intervals of 25-30 days. To assess the effectiveness of the treatment, two independent observers compared photographs and measured the reduction in terminal hair count before and after the final session. Clinical outcomes were evaluated using VAS questionnaires, and any adverse events were diligently recorded. RESULTS: The findings indicated that the utilization of the long-pulsed 800-nm diode laser was both safe and efficient in achieving hair removal during microtia ear reconstruction. As additional sessions were conducted, pain scores demonstrated a decline, while adverse reactions remained minimal. LIMITATIONS: This is a retrospective single-institution study. CONCLUSION: The application of a long-pulsed 800-nm diode laser has been proved to be a safe and effective method for removing hair during the process of microtia ear reconstruction, involving the use of a tissue expander and autologous costal cartilage. To achieve satisfactory results in hair removal, it was found necessary to repeat the shots procedure two to three times. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Copper-Catalyzed Enantioselective C(sp3 )-SCF3 Coupling of Carbon-Centered Benzyl Radicals with (Me4 N)SCF3.

In contrast with the well-established C(sp2 )-SCF3 cross-coupling to forge the Ar-SCF3 bond, the corresponding enantioselective coupling of readily available alkyl electrophiles to forge chiral C(sp3 )-SCF3 bond has remained largely unexplored. We herein disclose a copper-catalyzed enantioselective radical C(sp3 )-SCF3 coupling of a range of secondary/tertiary benzyl radicals with the easily available (Me4 N)SCF3 reagent. The key to the success lies in the utilization of chiral phosphino-oxazoline-derived anionic N,N,P-ligands through tuning electronic and steric effects for the simultaneous control of the reaction initiation and enantioselectivity. This strategy can successfully realize two types of asymmetric radical reactions, including enantioconvergent C(sp3 )-SCF3 cross-coupling of racemic benzyl halides and three-component 1,2-carbotrifluoromethylthiolation of arylated alkenes under mild reaction conditions. It therefore provides a highly flexible platform for the rapid assembly of an array of enantioenriched SCF3 -containing molecules of interest in organic synthesis and medicinal chemistry.

A general copper-catalysed enantioconvergent C(sp3)-S cross-coupling via biomimetic radical homolytic substitution.

Although α-chiral C(sp3)-S bonds are of enormous importance in organic synthesis and related areas, the transition-metal-catalysed enantioselective C(sp3)-S bond construction still represents an underdeveloped domain probably due to the difficult heterolytic metal-sulfur bond cleavage and notorious catalyst-poisoning capability of sulfur nucleophiles. Here we demonstrate the use of chiral tridentate anionic ligands in combination with Cu(I) catalysts to enable a biomimetic enantioconvergent radical C(sp3)-S cross-coupling reaction of both racemic secondary and tertiary alkyl halides with highly transformable sulfur nucleophiles. This protocol not only exhibits a broad substrate scope with high enantioselectivity but also provides universal access to a range of useful α-chiral alkyl organosulfur compounds with different sulfur oxidation states, thus providing a complementary approach to known asymmetric C(sp3)-S bond formation methods. Mechanistic results support a biomimetic radical homolytic substitution pathway for the critical C(sp3)-S bond formation step.

Safety and efficacy evaluation of botulinum toxin an injection by FITTER® microneedle to treat medial lower eyelid wrinkles.

BACKGROUND: Treatment for medial lower eyelid wrinkles is in great demand now. However, conventional injection of botulinum toxin A (BTX-A) often leads to serious complications. AIMS: We aim to evaluate the safety and efficacy of BTX-A injection with microneedle to treat medial lower eyelid wrinkles. METHODS: We collected clinical data of 16 patients to treat dynamic wrinkles on the medial aspect of the lower eyelid. Adverse effects at each stage of the treatment were recorded. We used VISIA to compare the static and dynamic wrinkles of the medial lower eyelid before and after treatment. Furthermore, patients and physicians evaluated the wrinkles with Kappa scores. RESULTS: All 16 patients completed the study. The objective evaluation indicator (the Ra variable given by VISIA) progressively and significantly decreased at 1 month and 3 months after treatment. The kappa scores given by patients and by surgeons were both significantly reduced after treatment. No adverse reactions, such as pouch prolapse, diplopia, and canthal tendon laxity, occurred at 1 week, 1 month, or 3 months after the treatment. CONCLUSION: BTX-A treatment of medial lower eyelid wrinkles with microneedle injection allows better control of the injection depth and reduces both the amount of BTX-A needed and the incidence of complications while maintaining the natural dynamic expression.

Copper-Catalyzed Enantioconvergent Radical C(sp3)-N Cross-Coupling of Activated Racemic Alkyl Halides with (Hetero)aromatic Amines under Ambient Conditions.

The enantioconvergent C(sp3)-N cross-coupling of racemic alkyl halides with (hetero)aromatic amines represents an ideal means to afford enantioenriched N-alkyl (hetero)aromatic amines yet has remained unexplored due to the catalyst poisoning specifically for strong-coordinating heteroaromatic amines. Here, we demonstrate a copper-catalyzed enantioconvergent radical C(sp3)-N cross-coupling of activated racemic alkyl halides with (hetero)aromatic amines under ambient conditions. The key to success is the judicious selection of appropriate multidentate anionic ligands through readily fine-tuning both electronic and steric properties for the formation of a stable and rigid chelating Cu complex. Thus, this kind of ligand could not only enhance the reducing capability of a copper catalyst to provide an enantioconvergent radical pathway but also avoid the coordination with other coordinating heteroatoms, thereby overcoming catalyst poisoning and/or chiral ligand displacement. This protocol covers a wide range of coupling partners (89 examples for activated racemic secondary/tertiary alkyl bromides/chlorides and (hetero)aromatic amines) with high functional group compatibility. When allied with follow-up transformations, it provides a highly flexible platform to access synthetically useful enantioenriched amine building blocks.

Exploring the motivations for pursuing operative labiaplasty in Chinese patients.

This study aimed to investigate the motivations for Chinese patients seeking operative labiaplasty. Data was collected from January 2018 to December 2019 using a standardized questionnaire, which examined factors influencing patients' motivations, including aesthetic and functional reasons, as well as psychological factors. Of the 216 patients who responded to the questionnaire within 24 months, 22.2% cited cosmetic reasons, while 38.4% reported functional discomfort. Both functional and aesthetic reasons were cited by 35.2% of patients, while 4.2% reported psychological troubles. It is noteworthy that patients who sought surgical intervention for physical complaints did so as a personal decision, and only 6.3% of patients seeking labiaplasty for cosmetic reasons were influenced by their sexual partner. Additionally, 7.9% and 66.7% of patients with other motivations were influenced by their male spouse, while 2.6% and 33.3% were influenced by the media. In conclusion, this study suggests that most Chinese patients seek labiaplasty for functional reasons, with few being influenced by sexual partners or media.Impact statementWhat is already known on this subject? The growing demand and interest in labiaplasty surgery has been widely acknowledged. Existing reports from western countries have highlighted that aesthetic concerns are the primary motivations behind patients' requests for this surgical intervention. However, there is limited information available regarding the factors influencing Chinese patients' decisions to undergo labiaplasty, as China has a large population. Therefore, the specific reasons behind Chinese patients' requests for labiaplasty are not well understood.What do the results of this study add? This clinical study focuses on the perspectives of eastern women regarding labia reduction surgery, contributing to the existing literature on this topic. Notably, this study is one of the few that examines the request for surgical reduction of hypertrophy of the labia minora and highlights that not all patients undergo surgical intervention purely for personal reasons.What are the implications of these findings for clinical practice and/or further research? The implications of these findings for clinical practice and further research are significant. Given the increasing demand for labiaplasty, gynecologists in Australia, Western Europe, the United States, and New Zealand are likely to encounter a rising number of women seeking labial reduction surgery. Similarly, labiaplasty has become an increasingly popular cosmetic surgery procedure in China. This study's results differ from previous research, which suggested that functional concerns were the primary motivation for women seeking to undergo labiaplasty. The request for pursuing labiaplasty is influenced not only by personal preferences but also by external factors. Therefore, a comprehensive evaluation before considering the procedure is crucial, and if practitioners are unsure, multidisciplinary specialized evaluation should be considered.

Copper-Catalyzed Enantioconvergent Radical C(sp3 )-N Cross-Coupling: Access to α,α-Disubstituted Amino Acids.

Transition-metal catalyzed enantioconvergent cross-coupling of tertiary alkyl halides with ammonia offers a rapid avenue to chiral unnatural α,α-disubstituted amino acids. However, the construction of chiral C-N bonds between tertiary-carbon electrophiles and nitrogen nucleophiles presented a great challenge owing to steric congestion. We report a copper-catalyzed enantioconvergent radical C-N cross-coupling of alkyl halides with sulfoximines (as ammonia surrogates) under mild conditions by employing a chiral anionic N,N,N-ligand with a long spreading side arm. An array of α,α-disubstituted amino acid derivatives were obtained with good efficiency and enantioselectivity. The synthetic utility of the strategy has been showcased by the elaboration of the coupling products into different chiral α-fully substituted amine building blocks.

Enantioconvergent Cu-catalysed N-alkylation of aliphatic amines.

Chiral amines are commonly used in the pharmaceutical and agrochemical industries1. The strong demand for unnatural chiral amines has driven the development of catalytic asymmetric methods1,2. Although the N-alkylation of aliphatic amines with alkyl halides has been widely adopted for over 100 years, catalyst poisoning and unfettered reactivity have been preventing the development of a catalyst-controlled enantioselective version3-5. Here we report the use of chiral tridentate anionic ligands to enable the copper-catalysed chemoselective and enantioconvergent N-alkylation of aliphatic amines with α-carbonyl alkyl chlorides. This method can directly convert feedstock chemicals, including ammonia and pharmaceutically relevant amines, into unnatural chiral α-amino amides under mild and robust conditions. Excellent enantioselectivity and functional-group tolerance were observed. The power of the method is demonstrated in a number of complex settings, including late-stage functionalization and in the expedited synthesis of diverse amine drug molecules. The current method indicates that multidentate anionic ligands are a general solution for overcoming transition-metal-catalyst poisoning.

Cu(I)-Catalyzed Chemo- and Enantioselective Desymmetrizing C-O Bond Coupling of Acyl Radicals.

Transition-metal-catalyzed enantioselective functionalization of acyl radicals has so far not been realized, probably due to their relatively high reactivity, which renders the chemo- and stereocontrol challenging. Herein, we describe Cu(I)-catalyzed enantioselective desymmetrizing C-O bond coupling of acyl radicals. This reaction is compatible with (hetero)aryl and alkyl aldehydes and, more importantly, displays a very broad scope of challenging alcohol substrates, such as 2,2-disubstituted 1,3-diols, 2-substituted-2-chloro-1,3-diols, 2-substituted 1,2,3-triols, 2-substituted serinols, and meso primary 1,4-diols, providing enantioenriched esters characterized by challenging acyclic tetrasubstituted carbon stereocenters. Partnered by one- or two-step follow-up transformations, this reaction provides a convenient and practical strategy for the rapid preparation of chiral C3 building blocks from readily available alcohols, particularly the industrially relevant glycerol. Mechanistic studies supported the proposed C-O bond coupling of acyl radicals.

Copper-Catalyzed Chemo- and Enantioselective Radical 1,2-Carbophosphonylation of Styrenes.

The copper-catalyzed enantioselective radical difunctionalization of alkenes from readily available alkyl halides and organophosphorus reagents possessing a P-H bond provides an appealing approach for the synthesis of α-chiral alkyl phosphorus compounds. The major challenge arises from the easy generation of a P-centered radical from the P-H-type reagent and its facile addition to the terminal side of alkenes, leading to reverse chemoselectivity. We herein disclose a radical 1,2-carbophosphonylation of styrenes in a highly chemo- and enantioselective manner. The key to the success lies in not only the implementation of dialkyl phosphites with a strong bond dissociation energy to promote the desired chemoselectivity but also the utilization of an anionic chiral N,N,N-ligand to forge the chiral C(sp3 )-P bond. The developed Cu/N,N,N-ligand catalyst has enriched our library of single-electron transfer catalysts in the enantioselective radical transformations.

Cu-catalysed enantioselective radical heteroatomic S-O cross-coupling.

The transition-metal-catalysed cross-coupling reaction has established itself as one of the most reliable and practical synthetic tools for the efficient construction of carbon-carbon/heteroatom (p-block elements other than carbon) bonds in both racemic and enantioselective manners. In contrast, development of the corresponding heteroatom-heteroatom cross-couplings has so far remained elusive, probably due to the under-investigated and often challenging heteroatom-heteroatom reductive elimination. Here we demonstrate the use of single-electron reductive elimination as a strategy for developing enantioselective S-O coupling under Cu catalysis, based on both experimental and theoretical results. The reaction manifests its synthetic potential by the ready preparation of challenging chiral alcohols featuring congested stereocentres, the expedient valorization of the biomass-derived feedstock glycerol, and the remarkable catalytic 4,6-desymmetrization of inositol. These results demonstrate the potential of enantioselective radical heteroatomic cross-coupling as a general chiral heteroatom-heteroatom formation strategy.

Synthesis of α-Quaternary ß-Lactams via Copper-Catalyzed Enantioconvergent Radical C(sp3 )-C(sp2 ) Cross-Coupling with Organoboronate Esters.

The copper-catalyzed enantioconvergent radical C(sp3 )-C(sp2 ) cross-coupling of tertiary α-bromo-ß-lactams with organoboronate esters could provide the synthetically valuable α-quaternary ß-lactams. The challenge arises mainly from the construction of sterically congested quaternary stereocenters between the tertiary alkyl radicals and chiral copper(II) species. Herein, we describe our success in achieving such transformations through the utilization of a copper/hemilabile N,N,N-ligand catalyst to forge the sterically congested chiral C(sp3 )-C(sp2 ) bond via a single-electron reduction/transmetalation/bond formation catalytic cycle. The synthetic potential of this approach is shown in the straightforward conversion of the corresponding products into many valuable building blocks. We hope that the developed catalytic cycle would open up new vistas for more enantioconvergent cross-coupling reactions.

Copper-Catalyzed Enantioconvergent Radical C(sp3)-N Cross-Coupling to Access Chiral α-Amino-ß-lactams.

A copper-catalyzed enantioconvergent radical C(sp3)-N cross-coupling of racemic tertiary α-bromo-ß-lactams with aromatic amines is developed under mild thermal reaction conditions. The use of a sterically demanded oxazoline-derived sulfonamide N,N,N-ligand is crucial for the reaction initiation and effective enantio-discrimination of the azetidinone-derived cyclic alkyl radicals. The strategy provides an attractive approach to access chiral α-amino-ß-lactams, an important structural motif in many biologically active molecules. Preliminary mechanistic studies support the formation of azetidinone-derived alkyl radicals from the L*Cu(I)-amido complex and α-bromo-ß-lactams.

Ligand Development for Copper-Catalyzed Enantioconvergent Radical Cross-Coupling of Racemic Alkyl Halides.

The enantioconvergent cross-coupling of racemic alkyl halides represents a powerful tool for the synthesis of enantioenriched molecules. In this regard, the first-row transition metal catalysis provides a suitable mechanism for stereoconvergence by converting racemic alkyl halides to prochiral radical intermediates owing to their good single-electron transfer ability. In contrast to the noble development of chiral nickel catalyst, copper-catalyzed enantioconvergent radical cross-coupling of alkyl halides is less studied. Besides the enantiocontrol issue, the major challenge arises from the weak reducing capability of copper that slows the reaction initiation. Recently, significant efforts have been dedicated to basic research aimed at developing chiral ligands for copper-catalyzed enantioconvergent radical cross-coupling of racemic alkyl halides. This perspective will discuss the advances in this burgeoning area with particular emphasis on the strategic chiral anionic ligand design to tune the reducing capability of copper for the reaction initiation under thermal conditions from our research group.