Benzenesulfenyl triflate

A variety of other activating systems have been employed for the promotion of sulfoxide-based glycosylation reactions, but none have been studied to the same extent as the triflic-anhydride-mediated reaction [86]. One of the most potent activators, benzenesulfenyl triflate, a by-product of the activation with triflic anhydride, has been shown to bring about rapid conversion of sulfoxides into glycosyl triflates [280]. Unfortunately, this reagent is unstable and has to be prepared in situ from silver triflate and benzenesulfenyl chloride. 

Although the existence of glycosyl triflates has only been demonstrated for the triflic anhydride and benzenesulfenyl triflate promoter systems, presumably the same intermediates may be invoked on preactivation with other triflate-incorporat-ing systems such as TMSOTf (Scheme 4.42) [332] and triflic add (Scheme 4.43) [84,333]. 

Related Reagents. Benzenesulfenyl Triflate (PhSOTf) S-(4-Methoxyphenyl) Benzenethiosulfinate (MPBT). ... 

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