nBu4NI-Catalyzed oxidative imidation of ketones and imides for the synthesis of alpha-amino ketones were realized for the first time. The methodology is characterized by its wide substrate scope even for acetone with readily available phthalimide, saccharin and succinimide, which opens a new pathway for direct imidation of ketones.
Organocatalytic Amidation and Esterification of Aldehydes with Activating Reagents by a Cross-Coupling Strategy
作者:Bin Tan、Narihiro Toda、Carlos F. Barbas
DOI:10.1002/anie.201205921
日期:2012.12.7
Formation on demand: An organocatalytic cross‐coupling reaction of aldehydes with N‐hydroxyimides, hexafluoroisopropyl alcohol, and sulfonimides has been developed. The resulting active intermediates can be directly converted into amides or esters in one pot. This simple method makes use of readily available starting materials, and the newly discovered activatingreagents should find broad application
N-fluorobenzenesulfonimide (NFSI) toward the synthesis of diarylsulfones has been developed. The reaction represents a rare example of sulfonylation reaction using NFSI as an efficient sulfonyl donor and the first example of acid-mediated sulfonylation of unactivated arenes with NFSI via selective cleavage of S–N bonds. This protocol provides a concise approach for the construction of pharmaceutically
The reaction of sulfinic acid (1) with methanol in the presence of NCS-DMS gave methyl sulfinate (2) and methyl sulfonate (3) in 22% and 45% yields, respectively. Similarly, 1 reacted with morpholine under the same conditions to give the corresponding sulfinamide (5) and sulfonamide (6) in 23% and 50% yields. In these reactions, the disulfone (4) was also obtained as a minor product in some cases. The formation of sulfonic acid derivatives and disulfone was found to proceed through the intermediate formation of the sulfonyl chloride (7). The formation mechanism of sulfinic acid derivatives is also discussed.
oxidative C–H bond amidation of anilides with dibenzenesulfonimides mediated by PhI(OAc)2 under metal-free conditions provided para-amidated anilides with high selectivity and moderate to good yields. The reaction proceeded under mild or neutral conditions and it has good air and moisture tolerance. The method represents a novel and facile strategy for the synthesis of arylamines.