UMSETZUNGEN VON METALL- UND METALLOIDVERBINDUNGEN MIT MEHRFUNKTIONELLEN MOLEKUELEN. XXXV. CYCLISCHE UREIDOBORANE

Article abstract of DOI:10.1016/S0022-328X(00)89013-0

Reactions of N,N'-diorganylureas and N,N'-diorganylthioureas, respectively, with halo-organylboranes lead to hydrogen halide and mixtures of two reaction products.The mixtures consist of 1,3,5-triaza-2-boracyclohexane-dione-4,6 and-dithione-4,6 (A), and 1,3,5-triaza-2,6-dibora-cyclohexanone-4 and -thione-4 (B), respectively.In the case of II and V 1 -oxa-3,5-diaza-2,6-dibora-cyclohexanone-4 is obtained as a by-product.Further by-products are in the case of the reaction of N,N' -dimethylthiourea with trihaloboranes 1,3,5-trimethyl-2,4,6-trihaloborazines and in the synthesis of XIX cyclohexylisothiocyanate.Haloboranes split the N,N' -diorganylureas and N,N' -diorganylthioureas partially into isocyanate and isothiocyanate and primary amine.This explains the formation of the above-mentioned heterocycles A and B.XXII-XXVII exist, as indicated by ν(C=N) in their infrared spectra and by the 11B NMR spectra, as 6-organylimino-1-thia-3,5-diaza-2,4-diboracyclohexanes.The compounds are characterized analytically and spectroscopically (NMR: 1H, 11B; MS; IR).