29334-25-6Relevant academic research and scientific papers
Dirhodium-Catalyzed Enantioselective B?H Bond Insertion of gem-Diaryl Carbenes: Efficient Access to gem-Diarylmethine Boranes
Huang, Ming-Yao,Li, Xiao-Yu,Su, Yu-Xuan,Yang, Liang-Liang,Zhao, Yu-Tao,Zhu, Shou-Fei
supporting information, p. 24214 - 24219 (2021/10/07)
The scarcity of reliable methods for synthesizing chiral gem-diarylmethine borons limits their applications. Herein, we report a method for highly enantioselective dirhodium-catalyzed B?H bond insertion reactions with diaryl diazomethanes as carbene precursors. These reactions afforded chiral gem-diarylmethine borane compounds in high yield (up to 99 % yield), high activity (turnover numbers up to 14 300), high enantioselectivity (up to 99 % ee) and showed unprecedented broad functional group tolerance. The borane compounds synthesized by this method could be efficiently transformed into diaryl methanol, diaryl methyl amine, and triaryl methane derivatives with good stereospecificity. Mechanistic studies suggested that the borane adduct coordinated to the rhodium catalyst and thus interfered with decomposition of the diazomethane, and that insertion of a rhodium carbene (generated from the diaryl diazomethane) into the B?H bond was most likely the rate-determining step.
Polymer-supported (2,6-dichloro-4-alkoxyphenyl)(2,4-dichlorophenyl) methanol: A new linker for solid-phase organic synthesis
Kurosu, Michio,Biswas, Kallolmay,Crick, Dean C.
, p. 1141 - 1144 (2007/10/03)
(Chemical Equation Presented) An acid and base stable hydroxytetrachlorodiphenylmethyl (HTPM) linker is developed for polymer-supported organic synthesis. The linkers reported here are utilized for loading carboxylic acids, amines, alcohols, and phenols, and are stable to Bronsted and Lewis acids, Bronsted bases, and a wide variety of nucleophiles. However, the HTPM linkers can conveniently be cleaved by the solvolytic displacement reactions with 20% TFA.
Acid- and base-stable esters: A new protecting group for carboxylic acids
Kurosu, Michio,Biswas, Kallolmay,Narayanasamy, Prabagaran,Crick, Dean C.
, p. 2513 - 2516 (2008/02/13)
An acid- and base-stable protecting group for carboxylic acids is described. The esters of (2,6-dichloro-4-methoxyphenyl)(2,4-dichlorophenyl) methanol are stable to Bransted and Lewis acids, Bronsted bases, and a wide variety of nucleophiles; however, the esters can be conveniently deprotected by a solvolytic displacement reaction with 20% trifluoroacetic acid. Georg Thieme Verlag Stuttgart.
