Electrophotocatalysis Versus Indirect Electrolysis: Electrochemical Selenocyclization of 3-Aza-1,5-dienes Facilitated by Energy Transfer, Direct Photolysis or N-Hydroxyphthalimide.

Three hybrid electrochemical protocols, which involve the energy transfer, direct photolysis and N-hydroxyphthalimide catalyst, respectively, are presented for the selenylation/cyclization of the fragile substrates of 3-aza-1,5-dienes with diorganyl diselenides to afford 3-selenomethyl-4-pyrrolin-2-ones. The two electrophotocatalytic reactions and the indirect electrolysis one are both regioselective and external-oxidant- and transition-metal-free, and are associated with a broad substrate scope and high Se-economy, and all three methods are amenable to gram-scale syntheses, late-stage functionalizations, sunlight-induced experiments and all-solar-driven syntheses.

Catalyst-Controlled Regiodivergent and Enantioselective Formal Hydroamination of N,N-Disubstituted Acrylamides to α-Tertiary-α-Aminolactam and ß-Aminoamide Derivatives.

Enantioenriched α-tertiary-α-aminoacid and α-chiral-ß-aminoacid derivatives play an important role in biological science and pharmaceutical chemistry. Thus, the development of methods for their synthesis is highly valuable and yet remains challenging. Herein, an unprecedented catalyst-controlled regiodivergent and enantioselective formal hydroamination of N,N-disubstituted acrylamides with aminating agents has been developed, accessing enantioenriched α-tertiary-α-aminolactam and α-chiral-ß-aminoamide derivatives. Sterically-disfavored and electronically-disfavored enantioselective hydroamination of electron-deficient alkenes have been successfully tuned using different transition metals and chiral ligands. Notably, extremely hindered aliphatic α-tertiary-α-aminolactam derivatives were synthesized by Cu-H catalyzed asymmetric C-N bond forming with tertiary alkyl species. Enantioenriched α-chiral-ß-aminoamide derivatives have been accessed by Ni-H catalyzed anti-Markovnikov-selective formal hydroaminations of alkenes. This set of reactions tolerates a wide range of functional groups to deliver diverse α-tertiary-α-aminolactam and α-chiral-ß-aminoamide derivatives in good yields with high levels of enantioselectivity.

Regio- and Enantioselective Ni-Catalyzed Formal Hydroalkylation, Hydrobenzylation, and Hydropropargylation of Acrylamides to α-Tertiary Amides.

The development of enantioselective alkyl-alkyl cross-couplings with coinstantaneous formation of a stereogenic center without the use of sensitive organometallic species is attractive yet challenging. Herein, we report the intermolecular regio- and enantioselective formal hydrofunctionalizations of acrylamides, forging a stereogenic center α-position to the newly formed Csp3 -Csp3 bond for the first time. The use of a newly developed chiral ligand enables the electronically-reversed formal hydrofunctionalizations, including hydroalkylation, hydrobenzylation, and hydropropargylation, offering an efficient way to access diverse enantioenriched amides with a tertiary α-stereogenic carbon center which is facile to racemize. This operationally simple protocol allows for the anti-Markovnikov enantioselective hydroalkylation, and unprecedented hydrobenzylation, hydropropargylation under mild conditions with excellent functional group compatibility, delivering a wide range of amides with excellent levels of enantioselectivity.

Synthesis of γ-Pyrones from Formal [4 + 2] Cyclization of Ketene Dithioacetals with Acyl Chlorides.

A formal [4 + 2] cyclization of easily available ketene dithioacetals with acyl chlorides has been developed. Mediated by lithium bis(trimethylsilyl)amide, a series of γ-pyrones were obtained with a broad substrate scope. This unprecedented formal [4 + 2] cyclization provides a novel mode for ketene dithioacetals as versatile synthons. The synthesized γ-pyrones could be successfully transformed to 2-aryl/amino γ-pyrones and 2,3-dihydroimidazo[1,2-a]pyridin-7(1H)-ones mainly via the cleavage of the C-S bond.

Csp3-H bond functionalization of amines via tunable iminium ions: divergent synthesis of trifluoromethylated arylamines.

A series of tunable iminium ions, generated in situ by the condensation of 4-trifluoromethyl-p-quinols with cyclic amines, can lead to the divergent synthesis of trifluoromethylated arylamines in a single step via redox-neutral isomerization. The direct α- and ß-functionalization of saturated amines can be achieved regioselectively under mild conditions.

4-Trifluoromethyl-p-quinols as dielectrophiles: three-component, double nucleophilic addition/aromatization reactions.

In recent years, numerous methods have emerged for the synthesis of trifluoromethylated arenes based on the late-stage introduction of a trifluoromethyl group onto an aryl ring. In sharp comparison, the synthesis of trifluoromethylated arenes based on the pre-introduction of a trifluoromethyl group onto an "aromatic to be" carbon has rarely been addressed. It has been found that 4-trifluoromethyl-p-quinol silyl ethers, the readily available and relatively stable compounds, can act as dielectrophiles to be applied to multi-component reactions for the synthesis of various trifluoromethylated arenes. Catalyzed by In(OTf)3, 4-trifluoromethyl-p-quinol silyl ethers react with C-, N-, and S-nucleophiles, respectively, in a regiospecific 1,2-addition manner to generate the corresponding highly reactive electrophilic intermediates. Further reaction of the in-situ generated electrophiles with a C-nucleophile followed by spontaneous aromatization enables the construction of functionalized trifluoromethyl arenes. This three-component, double nucleophilic addition/aromatization reaction based on the pre-introduction of a trifluoromethyl group onto an "aromatic to be" carbon provides a divergent strategy for the synthesis of trifluoromethylated arenes under mild reaction conditions in a single operation.

Leiomyomas of the bilateral tunica albuginea of testes: a case report.

Leiomyoma of the bilateral testicular tunica albuginea is extremely rare. To our knowledge, there are only 3 definitely reported cases. This is the first report of bilateral testicular tunica albuginea leiomyomas as a potential cause of male infertility. Herein, we report a case of a 47-year-old man who presented with painless bilateral testicular masses for more than 30 years, besides he also suffered from unexplained infertility. The complete resection of the tumors was performed. The final pathological diagnosis was leiomyomas of the bilateral tunica albuginea. Postoperatively, the patient underwent testicular biopsy. Histopathology confirmed moderate atrophy of bilateral testes, and the number of spermatogenic cells in the seminiferous tubules were significantly decreased. In this case, bilateral testicular dysplasia is the root reason for the patient's infertility. Thus, despite the benign nature of bilateral testicular tunica albuginea leiomyomas, they may cause bilateral testicular hypoplasia and infertility in men. In the case of men with fertility requirements, early local mass excision is often necessary.