Synthesis of 5-Substituted 1-Hydroxy-1,2,3-triazoles through Directed Lithiation of 1-(Benzyloxy)-1,2,3-triazole
摘要:
1-(Benzyloxy)-1,2,3-triazole, prepared by selective benzylation of 1-hydroxy-1,2,3-triazole or by oxidative cyclization of 2-hydrazonoglyoxal O-benzyloxime, was metalated exclusively at the 5-position upon treatment with n-butyllithium. The anion formed reacted with a series of electrophiles. In this way carbon, halogen, sulfur, silicon, and tin substituents could be introduced at the 5-position. Subsequent removal of the benzyl group by palladium-catalyzed hydrogenolysis or by treatment with hydrochloric acid afforded the corresponding 5-substituted 1-hydroxy-1,2,3-triazoles.
Synthesis of 5-Substituted 1-Hydroxy-1,2,3-triazoles through Directed Lithiation of 1-(Benzyloxy)-1,2,3-triazole
摘要:
1-(Benzyloxy)-1,2,3-triazole, prepared by selective benzylation of 1-hydroxy-1,2,3-triazole or by oxidative cyclization of 2-hydrazonoglyoxal O-benzyloxime, was metalated exclusively at the 5-position upon treatment with n-butyllithium. The anion formed reacted with a series of electrophiles. In this way carbon, halogen, sulfur, silicon, and tin substituents could be introduced at the 5-position. Subsequent removal of the benzyl group by palladium-catalyzed hydrogenolysis or by treatment with hydrochloric acid afforded the corresponding 5-substituted 1-hydroxy-1,2,3-triazoles.
1-(Benzyloxy)-1,2,3-triazole, prepared by selective benzylation of 1-hydroxy-1,2,3-triazole or by oxidative cyclization of 2-hydrazonoglyoxal O-benzyloxime, was metalated exclusively at the 5-position upon treatment with n-butyllithium. The anion formed reacted with a series of electrophiles. In this way carbon, halogen, sulfur, silicon, and tin substituents could be introduced at the 5-position. Subsequent removal of the benzyl group by palladium-catalyzed hydrogenolysis or by treatment with hydrochloric acid afforded the corresponding 5-substituted 1-hydroxy-1,2,3-triazoles.