Carbon Homologation of 1-Alkynes Using Alkoxymethyl Esters Mediated by Dichlorobis(trifluoromethanesulfonato)titanium(IV)
作者:Yoo Tanabe
DOI:10.1246/bcsj.67.3309
日期:1994.12
Various 1-alkynes were converted to 1-alkoxy-3-chloro-2-alkenes using alkoxymethyl esters and dichlorobis(trifluoromethanesulfonato)titanium(IV) [TiCl2(OTf)2, titanium(IV) bis(triflate)]. This carbon homologation proceeded in the case of not only simple 1-alkynes but also for several 3- or 4-dimethylcarbamoyloxy-, 5-benzoyloxy-, 5-phenoxycarbonyloxy-, and 5-methoxycarbonyloxy-1-alkynes. Among them
A structure-reactivity correlation with three slopes in the elimination kinetics of 2-substituted ethyl<i>N</i>,<i>N</i>-dimethylcarbamates in the gas phase
a: the 2-substituted alkyl groups gave a good straight line when log (k/kCH3) vs σ* values (ρ* = − 1.94 ± 0.30, r = 0.977 at 360 °C) were plotted. Slope b: Polar2 substituents gave an approximate straight line with ρ* = − 0.12 ± 0.02, r = 0.936 at 360 °C. Slope c : the correlation of multiple bonded and electron-withdrawing substituents interposed by a methylene group at the 2-position of ethyl N,N-dimethylcarbamate