NOVEL HETEROCYCLES FROM ALKYLAMINO-BIS(TRIFLUOROMETHYL)BORANE, (CF3)(2)BNR(2), AND ISOCYANIDES - CRYSTAL AND MOLECULAR-STRUCTURE OF (NC)(CF3)(2)B-CENTER-DOT-NHME(2), (CF3)(2)B-NME(2)-B(CF3)-NET=C-C(NME(2))=NET AND (CF3)(2)B-NME(2)-B(CF3)(2)-CH-C(=NME(2))-N(CH(2)PH)-CH(PH)-N

Dialkylamino-bis(trifluoromethyl)boranes, (CF3)(2)BNR(2)(1) [R(1) = Me (A), Et (B)] react at -20 degrees C with (t)BuNC to form the respective adducts ((t)BuNC)(CF3)(2)BNR(2)(1)[R(1) = Me (I), Et (II)]. At 20 degrees C these eliminate isobutylene to yield the amine boranes (NC)(CF3)(2)B . NHR(2)(1) [R(1) = Me (III), Et (IV)]. (PrNC)-Pr-1 combines with A in a 2:1 ratio to yield the four-membered heterocycle (CF3)(2)B-NMe(2)-C(=(NPr)-Pr-i)-C(=(NPr)-Pr-i) (V) and in a 2:2 ratio to form (CF3)(2)B-NMe(2)-B(CF3)(2)-NR=C-C(NMe(2))-NR [R=Pr-i (VI)]. Heterocycles corresponding to VI with R = (n)Bu (VII), Et (VIII) and Me (IX) were obtained by the respective reactions of (n)BuNC, EtNC and MeNC with A. The reaction of PhCH(2)NC with A leads to the formation of the heterobicyclo-octane (CF3)(2)B-NMe(2)-B(CF3)(2)-CH-C(=NMe(2))-N(CH(2)Ph)-CH(Ph)-N (X). The novel boron compounds have been characterized by multinuclear NMR, IR and mass spectra. The structures of III, VIII and X have been investigated by single-crystal X-ray diffraction.