Protection of an alcohol with tert-butyldimethylsilyl chloride yields which protecting group?

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Multiple Choice

Protection of an alcohol with tert-butyldimethylsilyl chloride yields which protecting group?

Silyl protection of alcohols works by converting the O–H group into an Si–O bond. When an alcohol reacts with tert-butyldimethylsilyl chloride in the presence of a base, the alcohol is turned into the tert-butyldimethylsilyl ether. This protection is desirable because the TBDMS group is bulky, giving good stability under many reaction conditions, and it can be removed later with fluoride sources or strong acid. Other protecting strategies use different reagents and routes—forming a tert-butyl ether would come from alkylation, or a THP ether from protection with dihydropyran under acid—so they aren’t the product of using tert-butyldimethylsilyl chloride.

Silyl protection of alcohols works by converting the O–H group into an Si–O bond. When an alcohol reacts with tert-butyldimethylsilyl chloride in the presence of a base, the alcohol is turned into the tert-butyldimethylsilyl ether. This protection is desirable because the TBDMS group is bulky, giving good stability under many reaction conditions, and it can be removed later with fluoride sources or strong acid. Other protecting strategies use different reagents and routes—forming a tert-butyl ether would come from alkylation, or a THP ether from protection with dihydropyran under acid—so they aren’t the product of using tert-butyldimethylsilyl chloride.

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