一、酯与脂肪伯胺的交换

酯与脂肪伯胺的交换一般直接NEAT加热进行，对于低沸点的伯按胺直接用其作溶剂回流即可。有时两个反应底物物都是固体无法混溶时，将两者溶解到某一溶剂后再浓缩干即可混合均匀，一般的无溶剂加热反应最好一边抽真空一边反应。有时胺的位阻较大时，也不好交换，一般也可仲胺交换反应条件来进行。

在此有一点需要指出的，当我们用LAH还原酰胺和腈到胺时，最后的产物为胺的铝盐，如果我们用酯去淬灭反应时常常得到的是相应的酰胺，如用乙酸乙酯淬灭即得到相应的乙酰胺。

1 、脂肪胺胺解芳香酸酯示例

A solution of 50 mg (0.10 mmol)of 5-n-butyl-2-(5-carbomethoxy-2-chlorophenyl)-2, 3-dihydro-4-(2-fluoro-4-bromobanzyl)-1,2,4-triazol-3-onein 1 ml of n-butylaminewas stirred overnight at 65 "C.  After being cooled toroom temperature, volatiles were evaporated in vacuo.  The residue was flash chromatographed(gradient elution with 1-5% MeOH in CH₂C1₂) to yield 41 mg(76%) of a colorless, glassy solid.

二、酯与脂肪仲胺的交换

酯与脂肪仲胺的交换一般直接交换是不行的，但其可通过相应的氨的负离子来反应，如通过正丁基锂作碱，同样三甲基铝可用于这类交换反应。

三、酯与芳胺的交换

由于芳香胺的亲核性不是太强，因而与酯直接交换不太容易，一般需要200度的高温才能交换。但如果通过强碱将芳胺变为相应的负离子，其亲核能力大大加强，可以发生相应的酯交换反应。目前常用的碱为NaHMDS, NaOEt, BuLi,EtMgBr等。有文献报道在微波下，用KO^tBu作碱在没溶剂的情况下可一分钟内完成胺交换反应。通过AlMe3也可顺利地将芳胺和酯进行交换。以上多见于芳香的伯胺，很少有文献报道芳香的仲胺参与酯的交换反应的。但有文献报道二氢吲哚与三甲基铝的复合物无可与酯进行交换。

1 、脂肪胺氨解芳香酸酯示例

A 2M solution of trimethyl aluminium in hexane (1.9 mL)was added dropwise to a cold (0 ℃) solution of4-amino-benzonitrile (0.29 g, 2.46 mmol) in anhydrous dichloromethane (30 ml)under argon atmosphere. The mixture was warmed to room temperature and stirredat room temperature for 30 min. A solution of 4-methyl-3- (4-pyridin-4-yl-thiazol-2-ylamino) -benzoic acid methyl ester (0.80 g, 2.46 mmol)in anhydrous dichloromethane (30 mL) and added slowly, and the resultingmixture was heated at reflux for 5h. The mixture was cooled to 0.deg.C andquenched by dropwise addition of a 4N aqueous sodium hydroxide solution (3 mL).The mixture was extracted with dichloromethane (3x20 mL). The combined organiclayers were washed with brine (3x20 mL) and dried over anhydrous MgS04. N-(4-Cyano-phenyl)-4-methyl-3- (4- pyridin-4-yl-thiazol-2-ylamino) -benzamide isobtained in 98percent after trituration of the crude product in methanol.

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