New silylalkylborane compounds, useful for the production of ceramic powder, are prepared by reaction of a silane with a metal in an aprotic solvent followed by reaction with a borane compound

摘要

New silylalkylborane compounds are prepared by reaction of a silane with a metal at less than 50 deg C in an aprotic solvent to form a further silane which is then reacted with a borane at below 50 deg C. New silylalkylborane compounds of formula (1) are prepared by reaction of a silane of formula (2) with a metal, M, at less than 50 deg C in an aprotic solvent to form a silane of formula (3) which is then reacted with a borane of formula (4) at below 50 deg C. (R)3Si-C(R1)(R2)-B(R)2 (1) (R3)Si-C(R1)(R2)-X (2) (R)3Si-C(R1)(R2)-M(X)w (3) Y-B(R)2 (4) R = 1-20C hydrocarbon, H, halogen, NR'R'' or OR'; R', R'' = H or 1-20C hydrocarbon; R1, R2 = H, halogen, 1-20C hydrocarbon, NR'R'' or OR'; X = halogen; M = metal; Y = halogen, NR'R'' or OR' Independent claims are also included for the following: (i) a process for the production of a compound of formula (5) by reaction of a compound of formula (6) with elemental halogen or an organic acid halide; (ii) a silylalkylborazine of formula (7) prepared by reaction of a silylalkylborane of formula (1) with an amine N(R4)3 or ammonium salt HN(R4)3+; (iii) oligo or polycarbosilazanes, prepared from a compound of formula (1) or a compound of formula (7), having a structural unit of formula (8); (iv) a silicon-boron-carbonitride ceramic having N-Si-C-B-N structural units prepared by pyrolysis of an oligo- or polyborocarbosilazane or silylalkylborazine of formula (7) in an inert or ammonia-containing atmosphere at -200 to +2000 deg C followed by calcining in an inert or ammonia-containing atmosphere at 800-2000 deg C; (v) a composite ceramic containing dispersed SiC, Si3N4, BN, C and/or B4C prepared by heating a siliconboroncarbonitride ceramic at above 1400 deg C. (R)3Si-C(R1)(R2)-B(X)2 (5) (R)3Si-C(R1)(R2)-B(OR')(OR'') (6) R3 = H, halogen, N(R')(R'') or OR'; R4 = R', Sn(R asterisk )3 or Si(R asterisk )3; R asterisk = R2 or 1-20C hydrocarbon.