RESTRICTED ROTATION INVOLVING THE TETRAHEDRAL CARBON.XXI. DIRECT OBSERVATION OF HINDERED ROTATION ABOUT A Csp3–C(=O) BOND IN PERISUBSTITUTED 9-(1-METHOXYCARBONYL-1-METHYLETHYL)TRIPTYCENES BY1H NMR SPECTRA
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چکیده
منابع مشابه
Hindered rotation in N-methylformamide. A peptide-bond model system.
Barriers to rotation about the C-N bond in the cis and trans isomers of N-methylformamide have been determined by n.m.r. spectroscopy. Representative values are 20.7 and 22.0 kcal/mole. Arrhenius parameters have also been determined. These results are compared with C-N barriers for N,N-dimethylformamide and unsubstituted formamide. The data suggest that C-N rotational barriers for N-methyl amid...
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ژورنال
عنوان ژورنال: Chemistry Letters
سال: 1978
ISSN: 0366-7022,1348-0715
DOI: 10.1246/cl.1978.475