Alkyneboron difluorides

Yamaguchi and Hirao found that alkyneboron difluorides, which are prepared from the alkynide ion and boron trifluoride etherate, react with oxiranes to give the 2-alkynols (Scheme 15). The same research group also found that ring opening of oxetane could be accomplished, but in this case boron trifluoride had to be added as a Lewis acid (Scheme 15). 

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