[23586-77-8] · C4H11ClOSi · Chloromethyl Trimethylsilyl Ether · (MW 138.67)
(hydroxymethyl cation equivalent1)
Physical Data: only characterized by 1H and 13C NMR at -50 °C.
Solubility: sol dichloromethane.
Preparative Method: prepared in situ under nitrogen by addition of a cooled (-78 °C) solution of Sulfuryl Chloride (1 equiv) in dry dichloromethane (2 M) to a solution of ethyl (trimethylsilyloxy)methyl sulfide in dichloromethane (1 M).1
Handling, Storage, and Precautions: low stability; best prepared in situ at low temperature.
Chloromethyl trimethylsilyl ether, prepared in situ at -78 °C in dichloromethane, reacts with 1-(trimethylsilyloxy)cyclopentene (3 equiv) and a catalytic amount of Zinc Bromide (10 mol %) to give 2-hydroxymethylcyclopentanone in 71% yield (eq 1).1 Since the preparation of chloromethyl trimethylsilyl ether generates an equivalent amount of ethylsulfenyl chloride, 2-ethylthiocyclopentanone is also obtained. Overall, this reagent provides a method for a-hydroxymethylation of carbonyl compounds.
National Taiwan University, Taipei, Republic of China