Formation of Thioaldehyde Intermediates by Thermolysis of Sulfoxides Bearing Some Heteroaromatics
摘要:
Thermal reactions of phenacyl sulfoxide bearing heterocycles, such as a 2-benzothiazolyl or N-oxypyridyl group, in the presence of 2,3-dimethyl-1,3-butadiene afforded 6-benzoyl-5,6-dihydro-3,4-dimethyl-2H-thiapyran in good yield. This product is considered to be formed by the Diels-Alder reaction of a diene with thioaldehyde formed initially by the decomposition of sulfoxides.
Formation of Thioaldehyde Intermediates by Thermolysis of Sulfoxides Bearing Some Heteroaromatics
摘要:
Thermal reactions of phenacyl sulfoxide bearing heterocycles, such as a 2-benzothiazolyl or N-oxypyridyl group, in the presence of 2,3-dimethyl-1,3-butadiene afforded 6-benzoyl-5,6-dihydro-3,4-dimethyl-2H-thiapyran in good yield. This product is considered to be formed by the Diels-Alder reaction of a diene with thioaldehyde formed initially by the decomposition of sulfoxides.
nitrogen-containing heterocycles in the presence of 2,3-dimethyl-1,3-butadiene led to 6-benzoyl-5,6-dihydro-3,4-dimethyl-2H-thiapyran. This product was considered to be formed by the Diels-Alderreaction of the diene with thioaldehyde formed initially by the thermal decomposition of the sulfoxide.
A general and efficient method for the synthesis of 4-sulfenylated oxazoles is described. Trisubstituted oxazoles are obtained in good to excellent yields from β-keto sulfoxides and nitriles. The mechanistic study suggests that the reaction proceeds via the nucleophilic addition of nitriles to the in situ formed α-carbonyl cation followed by intramolecular cyclization.
Thermal reactions of phenacyl sulfoxide bearing heterocycles, such as a 2-benzothiazolyl or N-oxypyridyl group, in the presence of 2,3-dimethyl-1,3-butadiene afforded 6-benzoyl-5,6-dihydro-3,4-dimethyl-2H-thiapyran in good yield. This product is considered to be formed by the Diels-Alder reaction of a diene with thioaldehyde formed initially by the decomposition of sulfoxides.