Synthesis and transformations of triphenylpropargylphosphonium bromide
摘要:
A method of the s,mthesis of triphenylpropargylphosphonium bromide is developed. Its isomerization and hydration in various solvents are studied, and reactions with secondary arnines, tricthylamine, and triphenylphosphine are carried out. It is established that secondary arnines add to the intermediate allene isomer with subsequent migration ofthe formed double bond to the phosphorus atorn. The reaction of triethylamine with trir.henylpropargyl and triphenylethynyl bromides occurs similarly to alkaline hydrolysis involving attack of' the amine on the phosphorus atom. Triphenylphosphine fornis with triphenylpropar-ylphosphonium biomide a bis-salt with a terminal methylene group. Experimental evidence is obtained showinc -, that for plioi;phoxazole derivatives to form from oxiines derived from triphenyl(oxomethyl)phosphonium salts tha latter should bear an aryl substituent at the keto group.
Synthesis and X-ray crystal structure of (1S,3R,4S,1′S)-4-methyl-3-triphenyl-pnosphonium-1-[1′-methyl(methyiphenyl)]-2-hydrido-2-borazetidinium bromide—the first example of a four-membered C–B–N–C heterocycle
作者:Brian L. Booth、Nicholas J. Lawrence、Robin G. Pritchard、Humayan S. Rashid
DOI:10.1039/c39950000287
日期:——
The title compound and related derivatives are synthesised from enamino(triphenyl)phosphonium salts and borane, and converted into β-aminophosphonium salts and β-aminophosphine oxides containing two chiral centres.
A new and very simplesynthesis of 2-amino-1,3-butadienes is described through Wittig reaction of the phosphoranes generated “in situ” from the β-enamino phosphonium salts with aldehydes.