SYNTHESES VIA VINYL SULFONES .75. TRIFLONE CHEMISTRY .10. SCOPE AND LIMITATIONS OF FUNCTIONALIZED ACETYLENIC TRIFLONES IN THE DIRECT ALKYNYLATION OF C-H BONDS

Reactions of TIPS-substituted acetylenic triflones extends the versati lity of the trifluoromethyl radical mediated C-H alkynylation reaction , Alkynes bearing acetylenic or propargylic oxygen functionality canno t be prepared, but silyl ethers or chlorides in remote positions may b e carried through the reaction. Crown ethers are successfully monofunc tionalized and distal bis-acetylenes may be employed in the title reac tion. (C) 1997 Elsevier Science Ltd.