Abstract:
The long-range spin-spin coupling constants between the methyl and the ring protons in several methyl pyridines have been determined, with their signs. The INDOR technique was used for this purpose and a systematic method was developed applicable to these spin systems, which were all of the ABCX3 type. It was found that 6JH,CH3 and4JH,CH3 are negative, while 5JH,CH3 is positive, with |4J|>|6J|>|5J|. These results show the same trend as shown by investigations of previous authors in other cyclic compounds. © 1972.
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Citas:
---------- APA ----------
Kowalewski, V.J. & Contreras, R.H.
(1972)
. The signs of the long-range spin-spin coupling constants in methyl pyridines as determined by the INDOR technique. Journal of Magnetic Resonance (1969), 8(1), 101-113.
http://dx.doi.org/10.1016/0022-2364(72)90028-5---------- CHICAGO ----------
Kowalewski, V.J., Contreras, R.H.
"The signs of the long-range spin-spin coupling constants in methyl pyridines as determined by the INDOR technique"
. Journal of Magnetic Resonance (1969) 8, no. 1
(1972) : 101-113.
http://dx.doi.org/10.1016/0022-2364(72)90028-5---------- MLA ----------
Kowalewski, V.J., Contreras, R.H.
"The signs of the long-range spin-spin coupling constants in methyl pyridines as determined by the INDOR technique"
. Journal of Magnetic Resonance (1969), vol. 8, no. 1, 1972, pp. 101-113.
http://dx.doi.org/10.1016/0022-2364(72)90028-5---------- VANCOUVER ----------
Kowalewski, V.J., Contreras, R.H. The signs of the long-range spin-spin coupling constants in methyl pyridines as determined by the INDOR technique. 1972;8(1):101-113.
http://dx.doi.org/10.1016/0022-2364(72)90028-5