Facile one-pot amidation of carboxylic acids by amines catalyzed by triphenylstibine oxide/tetraphosphorus decasulfide (Ph3SbO/P4S10)

…, T Nakano, Y Yamada, H Matsuda

文献索引：Nomura, Ryoki; Nakano, Takahiro; Yamada, Yasuhiro; Matsuda, Haruo Journal of Organic Chemistry, 1991 , vol. 56, # 12 p. 4076 - 4078

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被引用次数: 31

摘要

mechanism. 2 Our results agree nicely. We calculate the migration barrier (a,) in ethylborane to be 23 kcal/mol (MP4SDTQ/6-31 G**//MP2/6-3 1 G**), whereas dissociation into ethylene and borane requires 31.5 kcal/mol. The latter process, however, is favored by entropy. For this model reaction, we calculate the free energies of activation to be nearly equal at 300 K, 22.5 kcal/mol. The dissociation mechanism prevails at higher temperatures, while ...