Unusual effects of steric hindrances in NMR spectra of o,o′-dialkylsubstituted benzylidene dichlorides
摘要:
It has been found that steric hindrances of the CHCl2 group rotation around C(Ar)-CHCl2 bond in o,o'-dialkylsubstituted benzylidene dichlorides call forth a non-equivalence of the alkyls in positions 2 and 6. The non-equivalence displays in H-1 and C-13 NMR spectra at room temperature and at -20 degrees-C. At the latter temperature, the spectra of 2,4,6-trimethyl-3-chloromethylbenzylidene dichloride and bis(dichloromethyl)mesitylene indicate the presence of two conformations, the assignment of signals having been accomplished for each of them.
Unusual effects of steric hindrances in NMR spectra of o,o′-dialkylsubstituted benzylidene dichlorides
摘要:
It has been found that steric hindrances of the CHCl2 group rotation around C(Ar)-CHCl2 bond in o,o'-dialkylsubstituted benzylidene dichlorides call forth a non-equivalence of the alkyls in positions 2 and 6. The non-equivalence displays in H-1 and C-13 NMR spectra at room temperature and at -20 degrees-C. At the latter temperature, the spectra of 2,4,6-trimethyl-3-chloromethylbenzylidene dichloride and bis(dichloromethyl)mesitylene indicate the presence of two conformations, the assignment of signals having been accomplished for each of them.
The present disclosure is drawn to an amine synergist including a tertiary benzylamine with a substituted benzene ring attached to a tertiary amine. The tertiary amine can be modified with multiple water soluble groups.
Synthesis of sterically hindered aromatic aldehydes
作者:A. P. Yakubov、D. V. Tsyganov、L. I. Belen'kii、M. M. Krayushkin
DOI:10.1007/bf00961246
日期:1991.7
Formylation of mesitylene, durene, and m-xylene derivatives containing electron-donor and electron-acceptor substituents by dichloromethyl methyl ether was studied in the presence of TiCl4. A series of functionally substituted sterically hindered benzaldehydes was prepared from the products of these reactions.
YAKUBOV, A. P.;TSYGANOV, D. V.;BELENKIJ, L. I.;KRAYUSHKIN, M. M., IZV. AN CCCP. CEP. XIM.,(1991) N, S. 1609-1615
作者:YAKUBOV, A. P.、TSYGANOV, D. V.、BELENKIJ, L. I.、KRAYUSHKIN, M. M.