Zinc(II) Catalyzed Conversion of Alkynes to Vinyl Triflates in the Presence of Silyl Triflates
نویسندگان
چکیده
The conversion of alkynes to their corresponding vinyl triflates in the presence of stoichiometric TMS-triflate was greatly facilitated by the triflate salt of several transition metal catalysts most especially Zn(OTf)2. Products are formed in high regioselectivity under mild conditions. Internal alkynes bearing an aryl substituent afford vinyl triflates with a modest preference for the Z-isomer especially with larger substituents. A mechanism is put forward to explain the unique role of silicon in this system.
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