Showing papers on "Dichlorophenylphosphine published in 1990"
TL;DR: Cycloaddition of dichlorophenylphosphine with 3,4-bis(methylene)-thiolane affords a bicyclic phospholenium salt.
Abstract: Cycloaddition of dichlorophenylphosphine with 3,4-bis(methylene)-thiolane affords a bicyclic phospholenium salt; further reactions with water and dihydrogen sulfide give new series of bicyclic phospholenes.
1 citations
TL;DR: A general methodology for the preparation of sterically hindered hydroxyaryl derivatives of both phosphorus and silicon is described in this paper, where a trisadduct tris(3,5-di-t-butyl-4-trimethylsilyloxyphenyl(diphenyl)phosphine) is described.
Abstract: A general methodology for the preparation of sterically hindered hydroxyaryl derivatives of both phosphorus and silicon is described. The reaction of 3,5-di-t-butyl-4-trimethylsilyloxyphenyllithium ( 4 ), which was prepared by the metalation of 1-bromo-3,5-di-t-butyl-4-trimethylsilyloxybenzene with n-butyllithium at −78°C, with chlorodiphenylphosphine gave the protected phenolic derivative 3,5-di-t-butyl-4-trimethylsilyloxyphenyl(diphenyl)phosphine ( 5 ). Similarly, the reaction of 4 with dichlorophenylphosphine and phosphorus trichloride afforded the bis- and tris-adducts, bis(3,5-di-t-butyl-4-trimethylsilyloxyphenyl)phenylphosphine ( 7a ) and tris(3,5-di-t-butyl-4-trimethylsilyloxyphenyl)phosphine ( 7b ), respectively. Aqueous hydrolysis of 5 and 7a , 7b gave the corresponding 3,5-di-t-butyl-4-hydroxyphenylphosphines 1b and 8a , 8b , respectively. The reaction of 4 with the dimethyl-, diphenyl-, and methyl-substituted dichlorosilanes 9a – c gave the corresponding bis(3,5-di-t-butyl-4-trimethylsilyloxyphenyl)silanes 10a – 10c . Removal of the trimethylsilyl protecting group with N,N,N,N -tetra-n-butylammonium fluoride trihydrate (TBAF, trihydrate) gave the corresponding bis(3,5-di-t-butyl-4-hydroxyphenyl)silanes 11a – 11c , respectively. In the case of 10c , besides the expected derivative 11c , the fluoro-substituted silane bis(3,5-di-t-butyl-4-hydroxyphenyl)methylfluorosilane ( 12 ) was isolated. A plausible mechanism for the formation of 12 involving a pentacoordinate siliconate anion intermediate or transition state 13 was suggested. The reaction of 4 with silicon(IV) chloride followed by aqueous hydrolysis gave the trisubstitution product tris(3,5-di-t-butyl-4-trimethylsilyloxyphenyl)silanol ( 14 ). Deprotection of 14 with TBAF · trihydrate gave the trisadduct tris(3,5-di-t-butyl-4-hydroxyphenyl)silanol ( 15 ).