Synthesis of novel hydropyrazolopyridine derivatives in solvent-free conditions via benzotriazole methodology
摘要:
The reaction between 5-[N-(benzotriazol-1-ylmethyl)amino]-3-tert-butyl-1-phenylpyrazole or 5-amino-4-(benzotriazol-1-ylmethyl)-3-tert-butyl-1-phenylpyrazole with some unactivated and electron-rich alkenes has followed heterocyclization reactions to yield hydropyrazolopyridines, under solvent-free conditions, as predicted by benzotriazole methodology in contrast with those results obtained under solution. The reaction mechanism was proposed after fully spectroscopic analysis of final products and intermediates. (C) 2004 Elsevier Ltd. All rights reserved.
An unexpected chemical behavior of 5-N-(benzotriazol-1-ylmethyl)amino-3-tert-butyl-1-phenylpyrazole
摘要:
A rearrangement product or a pyrazolic Troger's base were unexpectedly obtained when 5-N-(benzotriazol-1-ylmethyl)amino-3-tert-butyl-1-phenylpyrazole was treated with electron-rich alkenes with well protic or Lewis acid catalyst, respectively, when tetrahydropyrazolopyridines were expected according with the benzotriazole methodology. The structure of the products was confirmed by NMR and X-ray diffraction techniques. Mechanisms for their formation are also proposed. (C) 2002 Elsevier Science Ltd. All rights reserved.
The reaction between 5-[N-(benzotriazol-1-ylmethyl)amino]-3-tert-butyl-1-phenylpyrazole or 5-amino-4-(benzotriazol-1-ylmethyl)-3-tert-butyl-1-phenylpyrazole with some unactivated and electron-rich alkenes has followed heterocyclization reactions to yield hydropyrazolopyridines, under solvent-free conditions, as predicted by benzotriazole methodology in contrast with those results obtained under solution. The reaction mechanism was proposed after fully spectroscopic analysis of final products and intermediates. (C) 2004 Elsevier Ltd. All rights reserved.
An unexpected chemical behavior of 5-N-(benzotriazol-1-ylmethyl)amino-3-tert-butyl-1-phenylpyrazole
A rearrangement product or a pyrazolic Troger's base were unexpectedly obtained when 5-N-(benzotriazol-1-ylmethyl)amino-3-tert-butyl-1-phenylpyrazole was treated with electron-rich alkenes with well protic or Lewis acid catalyst, respectively, when tetrahydropyrazolopyridines were expected according with the benzotriazole methodology. The structure of the products was confirmed by NMR and X-ray diffraction techniques. Mechanisms for their formation are also proposed. (C) 2002 Elsevier Science Ltd. All rights reserved.