AN UNUSUAL REACTION PRODUCT FROM A 1,3-DIBOROLENE AND TETRACARBONYLNICKEL. STRUCTURE OF A BIS(ALLYL)NICKEL COMPLEX

Article abstract of DOI:10.1016/S0022-328X(00)80135-7

The bis(allyl)nickel complex (η³-3-vinyl-2,4,5,6-tetraethyl-1-oxa-2,6-diboracyclohexenyl)(η³-2,3,4,5,6-pentaethyl-1-oxa-2,6-diboracyclohexenyl)nickel(IV) is formed by initial insertion of CO from Ni(CO)4 into the five-membered 1,3--diborolene I, to give a six-membered ring.Subsequent exchange of the CH-CH3 group of I for the oxygen atom of the inserted CO and migration of a hydrogen atom from the group of one ring to that of the other results in formation of the bis<1-oxa-2,6-diboracyclohexenyl>nickel, IV, having one vinyl and nine ethyl substituents.An X-ray structural analysis of IV shows the non-planarity of the C3B2O rings; the boron and oxygen atoms lie 0.4 and 0.7 Angstroem, respectively, away from the best plane through the allyl carbon atoms.IV crystallizes in the space group P2₁/n with a = 9.065(2), b = 16.264(3), c = 10.187(2) Angstroem, β = 104.28(1) deg, and Z = 2.