Wang, Dengjin published the artcileOne-Carbon Chain Extension of Esters to α-Chloroketones: A Safer Route without Diazomethane, Name: trimethyloxosulphonium chloride, the publication is Journal of Organic Chemistry (2004), 69(5), 1629-1633, database is CAplus and MEDLINE.
The reaction of a variety of Me 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-chloro ketones. This sequence has been utilized to convert the Me 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 Me ester, epimerization occurs so that the use of a more reactive aryl ester is required. This chem. provides a practical route to α-chloroketones that avoids the use of toxic and explosive diazomethane.
Journal of Organic Chemistry published new progress about 5034-06-0. 5034-06-0 belongs to chlorides-buliding-blocks, auxiliary class Salt,Aliphatic hydrocarbon chain, name is trimethyloxosulphonium chloride, and the molecular formula is C11H14O2, Name: trimethyloxosulphonium chloride.
Referemce:
https://en.wikipedia.org/wiki/Chloride,
Chlorides – an overview | ScienceDirect Topics