单词	amide
释义	amide /ˈeɪmʌɪd / /ˈamʌɪd / noun Chemistry 1An organic compound containing the group —C(O)NH2, derived from ammonia by replacement of a hydrogen atom by an acyl group.Secondary and tertiary amides are prepared by reacting primary amides or nitriles with organic acids.... The resulting ester was saponified under basic conditions to the free acid, converted to the acyl chloride with thionyl chloride, and then to the amide with anhydrous ammonia gas. The ester functional group can also be split by ammonia to give amides and alcohols. 1.1A compound derived from ammonia by replacement of a hydrogen atom by a metal, containing the anion NH2−: [with modifier]: sodium amide... On the other hand, the permeability of the membrane for small uncharged solutes such as low molecular weight alcohols, amides, ketones etc., did not change. Nitriles are formed by heating amides with phosphorous pentoxide or by treating organic halogen compounds with sodium cyanide. Primary amides are weakly basic and can form compounds with metals such as sodium, potassium, mercury, and cadmium, although heavy metal amides can be explosive. Origin Mid 19th century: from ammonia + -ide.
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