159141-65-8Relevant academic research and scientific papers
One-Carbon Chain Extension of Esters to α-Chloroketones: A Safer Route without Diazomethane
Wang, Dengjin,Schwinden, Mark D.,Radesca, Lilian,Patel, Bharat,Kronenthal, David,Huang, Ming-Hsing,Nugent, William A.
, p. 1629 - 1633 (2007/10/03)
The reaction of a variety of methyl esters with dimethylsulfoxonium methylide at 0-25 °C affords the chain-extended β-keto dimethylsulfoxonium ylides. Subsequent treatment with hydrogen chloride in THF proceeds with loss of DMSO to afford the corresponding α-chloroketones. This sequence has been utilized to convert the methyl esters of CBZ-protected alanine and valine to the anti N-protected α-amino epoxides, which are important pharmaceutical intermediates. When the same protocol is applied to BOC-protected phenylalanine methyl ester, epimerization occurs so that the use of a more reactive aryl ester is required. This chemistry provides a practical route to α-chloroketones that avoids the use of toxic and explosive diazomethane.
Stereocontrolled synthesis of erythro N-protected α-amino epoxides and peptidyl epoxides
Albeck, Amnon,Persky, Rachel
, p. 6333 - 6346 (2007/10/02)
N-protected α-amino epoxides of erythro configuration, derived from α-amino acids, were synthesized in a stereoselective manner. The erythro (2S,3S), configuration was achieved by the synthetic sequence: amino acid -> haloketone -> halohydrin -> epoxide. A mechanistic explanation for the observed stereoselectivity is presented. This stereoselective synthetic approach was applied to the synthesis of a variety of short peptidyl epoxides, bearing a predefined absolute configuration of the chiral epoxide moiety.
