88691-98-9Relevant academic research and scientific papers
1,3-Dipolar cycloadditions, 117. Reactions of thiobenzophenone S- methylide with thiocarbonyl compounds
Huisgen, Rolf,Li, Xingya,Mloston, Grzegorz,Fulka, Claudia
, p. 1695 - 1702 (2007/10/03)
2,5-Dihydro-2,2-diphenyl-1,3,4-thiadiazole (4) eliminates N2 at -45 °C and generates thiobenzophenone S-methylide (5), which is intercepted by dipolarophiles. The 1,3-cycloadditions of 5 with thiones (aromatic and aliphatic thioketones, dithioesters, trithiocarbonate) furnish 1,3- dithiolanes 7, in which the substituents, even voluminous ones, appear in the proximal 4- and 5-positions. The reaction of 5 with adamant-anethione furnishes 7h and 4,4,5,5-tetraphenyl-1,3-dithiolane (7a) in a ratio of 4:1; a methylene transfer is involved, and the mechanistic pathways are discussed. The cycloadduct 7f originating from 5 and diphenyl trithiocarbonate undergoes an isomerization which consists of ionization and ring-opening leading to a ketene dithioacetal structure.
NEW REACTIONS OF THIOBENZOPHENONE S-METHYLIDE
Xingya, Li,Huisgen, Rolf
, p. 4181 - 4184 (2007/10/02)
2,2-Diphenyl-1,3,4-thiadiazoline, prepared from thiobenzophenone and diazomethane at -78 deg C, extrudes N2 at -45 deg C and allows to study in situ 1,3-cycloadditions of thiobenzophenone S-methylide (3) with electrophilic C=S, C=C, CC, and N=N bonds.
THE ACTIVITY SCALE OF DIPOLAROPHILES VERSUS THIOBENZOPHENONE S-METHYLIDE
Huisgen, Rolf,Xingya, Li
, p. 4185 - 4188 (2007/10/02)
Competition experiments of pairs of dipolarophiles for thiobenzophenone (2) furnish relative rate constants which reveal an unusually high selectivity of the nucleophilic 1,3-dipole, in accordance with Sustmann's PMO concept.
