81233-30-9Relevant articles and documents
Preparation and reactions of bis(aminoboryl) oxides
Komorowska,Niedenzu,Weber
, p. 289 - 294 (2008/10/08)
Bis(aminoboryl) oxides (=1,3,2-diboroxanes) of the general type [(CH3)2N]RBOBR[N(CH3)2] (1a, R = N(CH3)2; 1b, R = C2H5, 1c, R = C6H5) have been prepared by the controlled hydrolysis of (dimethylamino)chloroboranes, (CH3)2NBClR. The compounds rearrange at elevated temperatures in an equilibrium reaction with the formation of boroxins, (RBO)3, and bis(dimethylamino)boranes, [(CH3)2N]2BR, a reaction that can also be used for the preparation of compounds of type 1. However, irreversible decomposition of 1 by organyl group migration to yield (dimethylamino)diorganylboranes, (CH3)2NBR2, and B,B′,B″-tris(dimethylamino)boroxin, [(CH3)2NBO]3, has also been observed at elevated temperatures. Transamination reactions of 1 have been utilized for the preparation of additional bis(aminoboryl) oxides, e.g., (C4H8N)(C6H5)BOB(C6H 5)(NC4H8) (2, C4H8NH = pyrrolidine), as well as for the synthesis of heterocyclic systems containing an annular BOB group, e.g., O(μ-RBNR′)2CX (4, X = O, S) from the reaction of 1 with (thio)ureas, (R′HN)2CX. The heterocycle O(μ-C2H5BNCH3)2BC 2H5 (3) was obtained from the reaction of 1b with C2H5B(NHCH3)2. Transamination of 1 with amides or aminoboronation reactions with isocyanates gave bicyclic systems (by intramolecular coordination) of the amidoborane, (R′CONR″)RBOBR(NR″COR′) (8), or ureidoborane, [(CH3)2NCONR′]RBOBR[NR′CON(CH 3)2] (6), type, respectively. A triply bridged species containing both three- and four-coordinate boron, RB(μ-NHCH3)(μ-OBRO)(μ-NCH3CHNCH3)BR (10), was obtained from the reaction of 1c with N-methylformamide.
UMSETZUNGEN VON METALL- UND METALLOIDVERBINDUNGEN MIT MEHRFUNKTIONELLEN MOLEKUELEN. XXXV. CYCLISCHE UREIDOBORANE
Maringgele, Walter
, p. 17 - 32 (2007/10/02)
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).
