53581-86-5Relevant articles and documents
Chemoselective Reduction of Sterically Demanding N,N-Diisopropylamides to Aldehydes
Xiao, Peihong,Tang, Zhixing,Wang, Kai,Chen, Hua,Guo, Qianyou,Chu, Yang,Gao, Lu,Song, Zhenlei
, p. 1687 - 1700 (2018/02/23)
A sequential one-pot process for chemoselectively reducing sterically demanding N,N-diisopropylamides to aldehydes has been developed. In this reaction, amides are activated with EtOTf to form imidates, which are reduced with LiAlH(OR)3 [R = t-Bu, Et] to give aldehydes by hydrolysis of the resulting hemiaminals. The non-nucleophilic base 2,6-DTBMP remarkably improves reaction efficiency. The combination of EtOTf/2,6-DTBMP and LiAlH(O-t-Bu)3 was found to be optimal for reducing alkyl, alkenyl, alkynyl, and 2-monosubstituted aryl N,N-diisopropylamides. In contrast, EtOTf and LiAlH(OEt)3 in the absence of base were found to be optimal for reducing extremely sterically demanding 2,6-disubstituted N,N-diisopropylbenzamides. The reaction tolerates various reducible functional groups, including aldehyde and ketone. 1H NMR studies confirmed the formation of imidates stable in water. The synthetic usefulness of this methodology was demonstrated with N,N-diisopropylamide-directed ortho-metalation and C-H bond activation.
Total Synthesis of Tambromycin by Combining Chemocatalytic and Biocatalytic C?H Functionalization
Zhang, Xiao,King-Smith, Emma,Renata, Hans
supporting information, p. 5037 - 5041 (2018/03/27)
A combination of genomic and metabolomic approaches recently resulted in the identification of a nonribosomal tetrapeptide tambromycin, which possesses promising antiproliferative activity and several unusual structural features, including a densely substituted indole, a methyloxazoline ring, and an unusual pyrrolidine-containing amino acid called tambroline. In this work, we identify a concise synthetic route to access tambromycin, which relies on the strategic use of biocatalytic and chemocatalytic C?H functionalization methods to prepare two key precursors to the natural product in an efficient and scalable manner. The success of our study highlights the benefits of applying the principles of biocatalytic retrosynthesis as well as C?H functionalization logic to the synthesis of complex molecular scaffolds.
A frank synthesis of alkyl-aryl ethers from 2-halobenzaldehydes and aromatic olefins without transition metal co-catalyst and ligand
Kumar, Balagani Sathish,Negi, Arvind S.
, p. 2340 - 2344 (2015/04/22)
An efficient synthesis of alkyl ethers has been developed for o-deactivated aryl halides and 1-halotetralenes. The method shows good regioselectivity towards ortho substituted halides. Alkali metal carbonates (Li2CO3/Na2CO3/K2CO3/Cs2CO3) have been used without a transition metal co-catalyst and ligand. The method is simple, straight-forward and proceeds to afford products in good isolated yields. The method holds potential for future applications in organic synthesis.
