Proton magnetic resonance emission in the intramolecular rearrangement of a tertiary amine oxide

Azetidines. 5. Reaction of 1,1,3,3-tetramethyl- and 1-benzyl-1,3,3-trimethylazetidinium ions with butyllithium and phenyllithium. Deuterium labeling as a mechanistic probe

“…Chem. In the present study, the proposed azomethine ylide (14) formed from 1 did not undergo an electrocyclic transformation to 1-neopentylaziridine. The absence of this product was established by gas chromatographic comparison of the retention time of authentic neopentylaziridine with the reaction products from 1.…”

Carbon-13 nuclear magnetic resonance studies of carbocations. 5. Effect of increasing electron demand on the carbon-13 chemical shifts of 3-aryl-3-pentyl and 2-aryl-2-adamantyl carbocations. Correlation of .DELTA..delta.C+ with enhanced substituent constants .sigma.C+

“…Transfer of the resulting dark colored solutions to the NMR tubes was achieved via a double-ended syringe needle. 15 The con- (12) Kelly, D. P.; Farquharson, G. J.; Giansiracusa, J. J.; Jensen, W. A.; Hügel, . M.; Porter, A. P.; Rainbow, I. J.; Timewell, P. H. J.…”

“…The "magic acid", SbF5/FS03H (1:1 molar ratio) concentration in the solution was 3 M. The concentration of the ion based on the alcohol added was ~0.5 M. Transfer of the solutions under nitrogen to an 8-mm NMR tube was achieved via a cooled double-ended syringe, as described previously. 15 Registry No. 3 (Z = 4-OCH3), 35144-43-5; 3 (Z = 4-CH3), 14290-14-3; 3 (Z = 4-F), 51804-44-5; 3 (Z = 4-Cl), 76499-76-8; 3 (Z = 3-CH3), 76499-77-9; 3 (Z = ), 14290-13-2; 3 (Z = 3-F), 76499-78-0; 3 (Z = 3-Cl), 76499-79-1; 3 (Z = 3-CF3), 76499-80-4; 3 (Z = 3,5-Cl2), 76499-81-5; 3 (Z = 4-CF3), 36043-26-2; 3 (Z = 3,5-(CF3)2), 76499-82-6; 4 (Z = 4-OCH3), 76499-83-7; 4 (Z = 4-CH3), 76499-84-8; 4 (Z = 4-F), 76499-85-9; 4 (Z = 4-Cl), 76499-86-0; 4 (Z = 3-CHg), 76499-87-1; 4 (Z = H), 76499-88-2; 4 (Z = 3-F), 76499-89-3; 4 (Z = 3-C1), 76499-90-6;…”

1,2-Anionic rearrangements. An example of mechanistic evolution

“…Subsequent observations of this CIDNP phenomenon in 1,2-anionic rearrangements have now been reported for additional examples of the Stevens rearrangement (31, 32), the sulfouium analog of the Stevens rearrangement,(33,34), and the Meisenheimer rearrangement(35). In many of these and analogous systems low yields of dimeric products, presumed to come from the radical intermediate, have been observed(36).…”