MECHANISTIC ASPECTS OF THE C-H ALKYNYLATION REACTION OF ACETYLENIC TRIFLONES - DETERMINATION OF PHENYL VERSUS CYCLOHEXYL MIGRATORY APTITUDEFOR A VINYLIDINE CARBENE
Js. Xiang et Pl. Fuchs, MECHANISTIC ASPECTS OF THE C-H ALKYNYLATION REACTION OF ACETYLENIC TRIFLONES - DETERMINATION OF PHENYL VERSUS CYCLOHEXYL MIGRATORY APTITUDEFOR A VINYLIDINE CARBENE, Tetrahedron letters, 37(30), 1996, pp. 5269-5272
C-13-2 labeled phenyl ethynyl triflone undergoes regiospecific C-H alk
ynylation upon reaction with cyclohexane. The C-13 label is found to b
e exclusively adjacent to the phenyl group in the product phenyl cyclo
hexyl acetylene, consistent with cyclohexyl radical addition at the al
pha-position. Control studies show preferential phenyl migration from
a vinylidine carbene, thus excluding the presence of such an intermedi
ate. Copyright (C) 1996 Elsevier Science Ltd