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1.
J Am Chem Soc ; 144(29): 13032-13038, 2022 07 27.
Article in English | MEDLINE | ID: mdl-35833781

ABSTRACT

We report a trifluoromethylarene reductive coupling method that dramatically expands the scope of difluorobenzylic substructures accessible via C-F bond functionalization. Catalytic quantities of a Lewis base, combined with a disilane reagent in formamide solvent, promotes the replacement of a single trifluoromethyl fluorine atom with a silylated hemiaminal functional group. The reaction proceeds through a difluorobenzyl silane intermediate that can also be isolated. Together, these defluorinated products are shown to provide rapid access to over 20 unique difluoroalkylarene scaffolds.


Subject(s)
Fluorine , Silanes , Catalysis , Fluorine/chemistry , Indicators and Reagents
2.
Chemistry ; 27(13): 4216-4229, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-32841442

ABSTRACT

Organic superbases are a distinct and increasingly utilized class of Brønsted base that possess properties complementary to common inorganic bases. This Concept article discusses recent applications of commercial organic superbases in modern synthetic methodologies. Examples of the advantages of organic superbases in three areas are highlighted, including the discovery of new base-catalyzed reactions, the optimization of reactions that require stoichiometric Brønsted base, and in high-throughput experimentation technology.

3.
J Org Chem ; 85(22): 14795-14801, 2020 11 20.
Article in English | MEDLINE | ID: mdl-32942856

ABSTRACT

Benzylic C-H borylation reactions are limited, requiring new approaches to exploit their reactivity for efficient selective functionalization. The recent development of phosphine-directed C-H borylation of arenes has now been extended to benzylic substrates, providing high yield of the mono- and geminal bis-borylation products. Attempts to borylate the C-H bond α to a benzylic ether or amine resulted in C-O and C-N borylation, followed by C-H borylation to provide geminal bis-borylated products.

4.
Ann Am Thorac Soc ; 17(7): 829-838, 2020 07.
Article in English | MEDLINE | ID: mdl-32223724

ABSTRACT

Rationale: Bronchoscopic lung volume reduction with Zephyr Valves improves lung function, exercise tolerance, and quality of life of patients with hyperinflated emphysema and little to no collateral ventilation.Objectives:Post hoc analysis of patient-reported outcomes (PROs), including multidimensional measures of dyspnea, activity, and quality of life, in the LIBERATE (Lung Function Improvement after Bronchoscopic Lung Volume Reduction with Pulmonx Endobronchial Valves used in Treatment of Emphysema) study are reported.Methods: A total of 190 patients with severe heterogeneous emphysema and little to no collateral ventilation in the target lobe were randomized 2:1 to the Zephyr Valve or standard of care. Changes in PROs at 12 months in the two groups were compared: dyspnea with the Transitional Dyspnea Index (TDI), focal score; the Chronic Obstructive Pulmonary Disease Assessment Test (CAT; breathlessness on hill/stairs); Borg; the EXAcerbations of Chronic pulmonary disease Tool-PRO, dyspnea domain; activity with the TDI, magnitude of task/effort/functional impairment, CAT (limited activities), and the St. George's Respiratory Questionnaire (SGRQ), activity domain; and psychosocial status with the SGRQ, impacts domain, and CAT (confidence and energy).Results: At 12 months, patients using the Zephyr Valve achieved statistically significant and clinically meaningful improvements in the SGRQ; CAT; and the TDI, focal score, compared with standard of care. Improvements in the SGRQ were driven by the impacts and activity domains (P < 0.05 and P < 0.001, respectively). Reduction in CAT was through improvements in breathlessness (P < 0.05), energy level (P < 0.05), activities (P < 0.001), and increased confidence when leaving home (P < 0.05). The TDI measures of effort, task, and functional impairment were uniformly improved (P < 0.001). The EXAcerbations of Chronic Pulmonary Disease Tool (EXACT)-PRO, dyspnea domain, was significantly improved in the Zephyr Valve group. Improvements correlated with changes in residual volume and residual volume/TLC ratio.Conclusions: Patients with severe hyperinflated emphysema achieving lung volume reductions with Zephyr Valves experience improvements in multidimensional scores for breathlessness, activity, and psychosocial parameters out to at least 12 months.Clinical trial registered with www.clinicaltrials.gov (NCT01796392).


Subject(s)
Bronchi/surgery , Pneumonectomy/methods , Prostheses and Implants , Pulmonary Emphysema/surgery , Quality of Life , Adult , Aged , Bronchoscopy , Exercise Tolerance , Female , Forced Expiratory Volume , Humans , Male , Middle Aged , Surveys and Questionnaires , Treatment Outcome
5.
Angew Chem Int Ed Engl ; 58(9): 2834-2838, 2019 Feb 25.
Article in English | MEDLINE | ID: mdl-30694597

ABSTRACT

Ambiphilic molecules, which contain a Lewis base and Lewis acid, are of great interest based on their unique ability to activate small molecules. Phosphine boronates are one class of these substrates that have interesting catalytic activity. Direct access to these phosphine boronates is described through the iridium-catalyzed C-H borylation of phosphines. An unconventional cationic iridium catalyst was identified as optimal for a range of phosphines, providing good yields and selectivity across a diverse class of phosphine boronates (isolated as the borane-protected phosphine). A complimentary catalyst system (quinoline-based silane ligand with [(COD)IrOMe]2 ) was optimal for biphenyl-based phosphines. Selective polyborylation was also shown providing bis- and tris-borylated phosphines. Deprotection of the phosphine boronate provided free ambiphilic phosphine boronates, which do not have detectable interactions between the phosphorus and boron atoms in solution or the solid state.

6.
Am J Respir Crit Care Med ; 198(9): 1151-1164, 2018 11 01.
Article in English | MEDLINE | ID: mdl-29787288

ABSTRACT

RATIONALE: This is the first multicenter randomized controlled trial to evaluate the effectiveness and safety of Zephyr Endobronchial Valve (EBV) in patients with little to no collateral ventilation out to 12 months. OBJECTIVES: To evaluate the effectiveness and safety of Zephyr EBV in heterogeneous emphysema with little to no collateral ventilation in the treated lobe. METHODS: Subjects were enrolled with a 2:1 randomization (EBV/standard of care [SoC]) at 24 sites. Primary outcome at 12 months was the ΔEBV-SoC of subjects with a post-bronchodilator FEV1 improvement from baseline of greater than or equal to 15%. Secondary endpoints included absolute changes in post-bronchodilator FEV1, 6-minute-walk distance, and St. George's Respiratory Questionnaire scores. MEASUREMENTS AND MAIN RESULTS: A total of 190 subjects (128 EBV and 62 SoC) were randomized. At 12 months, 47.7% EBV and 16.8% SoC subjects had a ΔFEV1 greater than or equal to 15% (P < 0.001). ΔEBV-SoC at 12 months was statistically and clinically significant: for FEV1, 0.106 L (P < 0.001); 6-minute-walk distance, +39.31 m (P = 0.002); and St. George's Respiratory Questionnaire, -7.05 points (P = 0.004). Significant ΔEBV-SoC were also observed in hyperinflation (residual volume, -522 ml; P < 0.001), modified Medical Research Council Dyspnea Scale (-0.8 points; P < 0.001), and the BODE (body mass index, airflow obstruction, dyspnea, and exercise capacity) index (-1.2 points). Pneumothorax was the most common serious adverse event in the treatment period (procedure to 45 d), in 34/128 (26.6%) of EBV subjects. Four deaths occurred in the EBV group during this phase, and one each in the EBV and SoC groups between 46 days and 12 months. CONCLUSIONS: Zephyr EBV provides clinically meaningful benefits in lung function, exercise tolerance, dyspnea, and quality of life out to at least 12 months, with an acceptable safety profile in patients with little or no collateral ventilation in the target lobe. Clinical trial registered with www.clinicaltrials.gov (NCT 01796392).


Subject(s)
Bronchi/surgery , Prostheses and Implants , Pulmonary Emphysema/surgery , Bronchoscopy , Equipment Design , Exercise Tolerance , Female , Forced Expiratory Volume , Humans , Male , Middle Aged , Surveys and Questionnaires , Treatment Outcome
7.
Clin Chest Med ; 24(3): 473-87, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14535221

ABSTRACT

Care of the long-term tracheostomy patient is changing. By moving the initiation of tracheostomy out of the operating room and shifting responsibility for the procedure to the medical specialist, more patients are undergoing tracheostomy for a wider spectrum of diagnoses. With much of the aftercare now directed by the medical specialist, successful reintegration of the long-term tracheostomy patient into a productive life is dependent upon the collaborative care of several disciplines directed by the specialist. To effectively care for these challenging patients, it is critical for the physician who performs tracheostomy to be aware of the new caregiving role that is now theirs.


Subject(s)
Aftercare/trends , Respiration, Artificial , Tracheostomy/rehabilitation , Caregivers , Home Care Services, Hospital-Based , Humans , Humidity , Nutritional Support , Patient Care Team , Physician's Role , Postoperative Care , Suction , Tracheostomy/adverse effects , Ventilator Weaning
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