SYNTHESIS OF BORYLINDENIDES - STRUCTURE OF I(N,N',N''-ME-3-1,3,5-C3H6N3)][1-C9H6(B(NME2)(2))]

Borylation of lithium indenide (LiInd) affords indenylboranes. With BC l(NMe2)(2) the primary allylic 1-indenyl derivative IndB(NMe2)(2) (1) readily rearranges to the more stable vinylic bis(dimethylamino)(3-ind enyl) borane 1'. With BCl(OCMe2)(2) the (1-indenyl)-1,3,2-dioxaborolan e IndB(OCMe2)(2) (2) is obtained. Both indenylboranes 1' and 2 readily undergo metalation when treated with lithium amides such as LiTMP or LDA to give 1-borylindenides Li[C9H6B(NMe2)(2)] [Li(3)] and Li[C9H6B(O CMe2)(2)] [Li(5)] in high yields. In the systems 1'/LiInd and 2/LiInd metalation equilibria are established with equlibrium constants K appr oximate to 1 (1'/LiInd) and K approximate to 1.4 (2/LiInd). The struct ure of the solvate [Li(TMHT)][1-C9H6{B(NMe2)(2)}] (4) (TMHT = N,N',N ' '-Me,-1,3,5-C3H6N3) has been confirmed by X-ray diffraction. (C) 1998 Elsevier Science S.A. All rights reserved.