溶液态和固态氨基苯并咪唑的13C和15N核磁共振谱。

13C and 15N NMR spectra of aminobenzimidazoles in solution and in the solid state.

作者信息

Angeles García M, Claramunt Rosa M, Solcan Tomás, Milata Viktor, Alkorta Ibon, Elguero José

机构信息

Departamento de Química Orgánica y Bio-Orgánica, Facultad de Ciencias, UNED, Senda del Rey 9, E-28040 Madrid, Spain.

出版信息

Magn Reson Chem. 2009 Feb;47(2):100-4. doi: 10.1002/mrc.2357.

DOI:10.1002/mrc.2357

PMID:19006105

Abstract

The (13)C [hexadeutero-dimethylsulfoxide (DMSO-d(6)), hexamethyl-phosphoramide (HMPA)-d(18)and solid-state] and (15)N (solid-state) NMR spectra of six C-aminobenzimidazoles have been recorded. The tautomerism of 4(7)-aminobenzimidazoles and 5(6)-aminobenzimidazoles has been determined and compared with B3LYP/6-311 + + G(d,p) calculations confirming the clear predominance of the 4-amino tautomer and the slight preference for the 6-amino tautomer. GIAO-calculated absolute shieldings compare well with experimental chemical shifts.

摘要

记录了六种C-氨基苯并咪唑的(13)C[十六氘代二甲基亚砜(DMSO-d(6))、六甲基磷酰胺(HMPA)-d(18)和固态]以及(15)N(固态)核磁共振谱。已确定4(7)-氨基苯并咪唑和5(6)-氨基苯并咪唑的互变异构现象，并与B3LYP/6-311++G(d,p)计算结果进行比较，证实了4-氨基互变异构体的明显优势以及6-氨基互变异构体的轻微偏好。GIAO计算的绝对屏蔽与实验化学位移比较吻合。