Patent GB-758168-A (GB)
Title: Organosilicon compounds
IPC: C07F7/08
Filed: 1954-09-06
Abstract: The invention comprises polysiloxanes, which are end-blocked by piperidine radicals, of the formula <FORM:0758168/IV(a)/1> where R1 is a monovalent hydrocarbon or halogenated aryl hydrocarbon radical, n is from 2 to 5 and m is 0 or an integer which may be upwards of 10,000.  They are prepared by copolymerizing the disiloxanes <FORM:0758168/IV(a)/2> (see Group IV (b)), with diorganosiloxanes, preferably using an alkali metal hydroxide catalyst.  Suitable diorganosiloxanes are dimethyl-, phenylmethyl -, stearylmethyl -, cyclohexylmethyl-, chlorophenylmethyl-, bis - trifluorotolyl -, bromo - xenylmethyl -, vinylmethyl -, vinylphenyl-, divinyl-, diphenyl-, ditolyl- and xenylethyl-siloxanes.  In the examples: (4) compounds of formula (1) are prepared in which R1 is methyl, n is 2 and m is 1, 2 and 3 and higher, by copolymerizing octamethylcyclotetrasiloxane with the disiloxane of formula (2) wherein n is 2, by heating for 3 days at 80 DEG  C. in the presence of KOH; (5) compounds of formula (1) in which one R1 is methyl and the other is phenyl, n is 3 and m is at least 1, are prepared by copolymerizing tetramethyltetraphenyltetrasiloxane with the disiloxane of formula (2) wherein n is 3; (6) compounds of formula (1) in which n is 5, one R1 is methyl and the other is dichlorophenyl and m is at least 1, are obtained by copolymerizing dichlorophenylmethylsiloxane with the disiloxane in which n is 5. Specification 684,295 is referred to.ALSO:The invention comprises organosilyl piperidines of the formula <FORM:0758168/IV(a)/1> where n is from 2 to 5 and R is methyl or phenyl, and siloxanes of the formula <FORM:0758168/IV(a)/2> where R1 is a monovalent hydrocarbon or halogenated aryl hydrocarbon radical and m is O or an integer.  The first compounds may be prepared by reacting silylamines of the formula RMe2Si(CH2)nNH2 with pentamethylene dibromide.  The disiloxanes (i.e. m = O in formula (2)) are prepared by reacting the compounds of formula (1) with conc. sulphuric acid, treating with water and making alkaline with an alkali metal hydroxide.  These disiloxanes may be copolymerized with diorganosiloxanes, preferably using an alkali metal hydroxide catalyst, to give the higher polysiloxanes.  In the examples (1) N-(b -trimethylsilylethyl)-piperidine is prepared from pentamethylene dibromide and b -trimethylsilylethylamine; (2) N-(g -trimethylsilylpropyl)-piperidine is similarly prepared; (3) the disiloxane <FORM:0758168/IV(a)/3> is prepared from the product of Example (1) and is copolymerized; (4) with octamethylcyclotetrasiloxane to give polysiloxanes of the formula (2) in which n is 2, m is 1, 2 and 3 and higher and R1 is methyl; (5) the disiloxane is prepared from the product of Example (2) and is copolymerized with tetramethyl-tetra-phenyltetrasiloxane to give compounds of the formula (2) in which one R1 is methyl and the other is phenyl, n is 3 and m is at least 1; (6) N-(5-phenyldimethylsilylpentyl)piperidine is prepared and is converted to the disiloxane which is copolymerized with dichlorophenylmethylsiloxane to give compounds of the formula (2) wherein n is 5, one R1 is methyl and the other is dichlorophenyl, and m is at least 1.  Specification 684,295 is referred to.