| 摘要 |
The invention concerns an improved method for obtaining organosilanes comprising the following steps: a redistribution reaction between a chlorinated organohydrogenosilane of formula (1) (R)a(H)b SiCl4-4-b and an organo-substituted and optionally chlorinated silane of formula (2) (R')cSiCl4-c, formulae in which: a = 1 or 2; b = 1 or 2; a + b </= 3; c = 1, 2, 3 or 4; the symbols R and R' are identical or different and represent each a linear or branched C1-C6 alkyl radical or a C6-C12 aryl radical; said redistribution reaction taking place in the presence of an effective amount of a catalyst consisting of a Lewis acid of formula (3) M(X)d in which: M represents a metal selected among Ti, Fe, Cu, Ag, Zn, Cd, Hg, Al, Ga, In, B ,Sn, Pb, Sb and Bi; X represents a halogen atom; d represents the valency of metal M; and separation by distillation of the chlorinated organohydrogenosilane resulting from the redistribution. Said method is characterised in that, after redistribution, at least a compound inhibiting the redistribution catalyst is brought in corresponding to the following definitions: it is selected among: (i) a silane of formula (R<1>)eSi(OR<2>)4-e (4) in which R<1> and R<2> can represent in particular alkyl or aryl radicals and e = 0, 1, 2 or 3; and (2i) a silicon resin, for example of the MQ, MDQ, TD or MDT type, having OR<4> terminal groups, in which R<4>= H, alkyl or aryl, carried by Si atoms of the M, D, and/or T structural units; it is used in proportions such that the ratio: r = number of metal M atom mols brought by the catalyst/number of mols of groups OR<2> or OR<4> brought by the inhibitor is not more than 1. |
