硝酸铋(III)五水合物[Bi(NO 3)3 ·5H 2 O]或氯化锆(IV)(ZrCl 4)已显示出可以催化1,2-二氰基氧杂环戊烷的亲核开环以及1,3的闭环-二亲核试剂,例如1 H -1,3-苯并咪唑-2-硫醇,5-苯基-4 H -1,2,4-三唑-3-硫醇和硫脲。这些反应导致与苯并咪唑或三唑衍生物缩合的杂环化合物的有效合成。所用的催化剂便宜,高效且可在环境温度下用于以1,3-二亲核试剂打开环氧化物,具有出色的区域选择性。
2-Aminothiazole and 2-aminothiazolinone derivatives
作者:Renata Toplak、Nina Lah、Julija Volmajer、Ivan Leban、Alenka Majcen Le Maréchal
DOI:10.1107/s0108270103015580
日期:2003.9.15
The reaction of different substituted alpha-cyanooxiranes with thiourea resulted in the formation of the 2-aminothiazolinone derivative 2-amino-5-(2,5-dimethoxyphenyl)-1,3-thiazol-4(5H)-one, C11H12N2O3S, (I), and the 2-aminothiazole derivative ethyl 2-amino-5-(2,5-dimethoxyphenyl)-1,3-thiazole-4-carboxylate, C14H16N2O4S, (II). The geometries of the two crystallographically independent molecules in (II) are nearly identical but mirror related. The crystal structures of both compounds contain two types of intermolecular hydrogen bonds.
Regioselective ring opening of 2,2-dicyanooxiranes by 1,3-dinucleophiles in the presence of Lewis acids such as bismuth(III) nitrate pentahydrate [Bi(NO3)3·5H2O] and zirconium(IV) chloride (ZrCl4)
or zirconium(IV) chloride (ZrCl4) has been shown to catalyze nucleophilic ring opening of 2,2-dicyanooxiranes along with ringclosure by 1,3-dinucleophiles such as 1 H -1,3-benzimidazole-2-thiol, 5-phenyl-4 H -1,2,4-triazole-3-thiol, and thioureas. These reactions led to efficient synthesis of heterocyclic compounds condensed with benzimidazole or triazole derivatives. The used catalysts are inexpensive
硝酸铋(III)五水合物[Bi(NO 3)3 ·5H 2 O]或氯化锆(IV)(ZrCl 4)已显示出可以催化1,2-二氰基氧杂环戊烷的亲核开环以及1,3的闭环-二亲核试剂,例如1 H -1,3-苯并咪唑-2-硫醇,5-苯基-4 H -1,2,4-三唑-3-硫醇和硫脲。这些反应导致与苯并咪唑或三唑衍生物缩合的杂环化合物的有效合成。所用的催化剂便宜,高效且可在环境温度下用于以1,3-二亲核试剂打开环氧化物,具有出色的区域选择性。