ISSN:
0749-1581
Keywords:
15N, 29Si and 119Sn NMR
;
3J(M15N)
;
Organometallic-substituted enamines
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
1H, 13C, 15N, 29Si and 119Sn NMR data (chemical shifts and coupling constants) are reported for the organometallic substituted enamines Me3Sn(Me3M)C=C(NEt2)CH2OMe [M = Sn (1), Ge (2), Si (3)], of which 2 and 3 are obtained as a mixture of E and Z isomers, and (Me3Sn)2C=C(NEt2)C≡CNEt2. Since there is no inverse linear relationship between δ13C(MC=) and δ15N, NC(pp)π interactions must be regarded as being very weak. All vicinal coupling constants, 3J(119Sn13C), 3J(119Sn15N) and 3J(29Si15N), across the C=C double bond show the expected stereochemical dependence, with | 3Jtrans | 〉 | 3Jcis |. To our knowledge, long-range couplings of this type, involving 15N, are reported for the first time. The magnitude of | 3J(119Sn15N)trans | exceeds the magnitude of | 1J(119Sn15N) | in most trimethyltin amides. A relationship between the magnitude of | 3J(119Sn15N) | and the orientation of the nitrogen lone electron pair is proposed.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1260290507
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