2,2-Diphenyl-1,3,4-thiadiazoline, prepared from thiobenzophenone and diazomethane at −78°C, extrudes N2 at −45°C and allows to study in situ 1,3-cycloadditions of thiobenzophenone S-methylide (3) with electrophilic CS, CC, CC, and NN bonds.
The activity scale of dipolarophiles versus thiobenzophenone s-methylide
作者:Rolf Huisgen、Li Xingya
DOI:10.1016/s0040-4039(00)88294-5
日期:——
Competition experiments of pairs of dipolarophiles for thiobenzophenone S-methylide () furnish relative rate constants which reveal an unusually high selectivity of the nucleophilic 1,3-dipole, in accordance with Sustmann's PMO concept.
Further contributions to the stereospecificity of 1,3-dipolar cycloadditions of thiocarbonyl ylides
作者:Rolf Huisgen、Eike Langhals、Heinrich Nöth
DOI:10.1016/s0040-4039(00)85241-7
日期:1986.1
The stereospecific cycloadditions of thiobenzophenone S-methylide () to dimethyl 2,3-dicyanofumarate and of thiocarbonylylide to maleonitrile contribute to the separation of electronic (HO-LU energy distances) and steric effects in the borderline region of competing concerted and two-step processes.