Theoretical Study of 13C Chemical Shifts Structures of Some ortho-Substituted 3-Anilino-2-nitrobenzo[b]thiophenes and 2-Anilino-3-nitrobenzo[b]thiophenes and Comparison with Experimental

✍ Scribed by Rezaei Sameti Mahdi

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 169 KB
• Volume: 29
• Category: Article
• ISSN: 0256-7660
• DOI: 10.1002/cjoc.201190072

✦ Synopsis

Abstract

^13^C NMR chemical shifts have been calculated for structures of some substituted 3‐anilino‐2‐nitrobenzo‐[b]thiophenes (2o) and 2‐anilino‐3‐nitrobenzo[b]thiophenes (3o) derivatives containing OH, NH~2~, OMe, Me, Et, H, F, Cl and Br. The molecular structures were fully optimized using B3LYP/6‐31G(d,p). The calculation of the ^13^C shielding tensors employed the GAUSSIAN 03 implementation of the gauge‐including atomic orbital (GIAO) and continuous set of gauge transformations (CSGT) by using 6‐311++G(d,p) basis set at density functional levels of theories (DFT). The isotropic and the anisotropy parameters of chemical shielding for all compounds are calculated. The predicted ^13^C chemical shifts are derived from equation δ=δ~0~+δ where δ is the chemical shift, δ is the absolute shielding, and δ~0~ is the absolute shielding of the standard TMS. Excellent linear relationships have been observed between experimental and calculated ^13^C NMR chemical shifts for all derivatives