7291-33-0Relevant articles and documents
Dynamic NMR: Field Dependence of the Coalescence Temperature and Temperature Dependence of T2 Relaxation Times in N,N-Dimethyltrichloroacetamide
Dimitrov, V. S.,Ladd, J. A.
, p. 529 - 532 (1985)
The field dependence of the 1H and 13C coalescence temperatures in N,N-dimethyltrichloroacetamide has been used to determine the most reliable activation parameters for internal rotation of the amide moiety.The results were found to be in excellent agreement with those obtained earlier by the double-fitting procedure and demonstrate its validity.Direct measurements of the T2 relaxation times of the methyl protons show that T2 depends exponentially on temperature.
Controlling Selectivity in the Synthesis of Z-α,β-Unsaturated Amidines by Tuning the N-Sulfonyl Group in a Rhodium(II) Catalyzed 1,2-H Shift
Boyer, Alistair,Martin, Matthew L.
supporting information, p. 5857 - 5861 (2021/11/27)
N2-Sulfonyl-α-diazo amidines can be synthesized by the reaction of electron rich alkynyl amines with electron poor sulfonyl azides through 1,3-dipolar cycloaddition that proceeds with perfect regioselectivity. In the presence of rhodium(II) carboxylate catalysts, denitrogenation occurs to give the corresponding metallocarbene but there are then two competing processes: 1,2–H shift and O-transfer from the sulfonyl group to the metallocarbene center. The outcome can be controlled using an electron poor nitrobenzenesulfonyl group and large carboxylate rhodium ligands to select for 1,2–H shift, forming α,β-unsaturated amidines in high yield and with excellent Z-selectivity.
