Hydantoins of the formula ##STR1## wherein R.sub.1 is hydrogen or alkyl of 1 to 8 carbon atoms, R.sub.2 is ##STR2## R.sub.3 is alkyl of 1 to 8 carbon atoms, and X is a straight or branched chain alkylene of 1 to 4 carbon atoms or a straight or branched chain alkylene of 3 to 6 carbon atoms containing an internal carbamido group; or R.sub.1 and R.sub.2 together are Y where Y is a straight or branched chain alkylene of 4 to 8 carbon atoms having a pendant ##STR3## ARE PREPARED BY REACTING FIRST .alpha.,.beta.-UNSATURATED ALDEHYDES OR KETONES WITH ALKYL PHOSPHITES TO FORM A PHOSPHONATE ALDEHYDE OR KETONE FOLLOWED BY A CLASSICAL Bucherer hydantoin synthesis.
式子为 ##STR1## 的Hydantoins,其中R.sub.1是氢或1至8个碳原子的烷基,R.sub.2是##STR2##,R.sub.3是1至8个碳原子的烷基,X是1至4个碳原子的直链或支链烷基,或者是包含一个内部carbamido基团的3至6个碳原子的直链或支链烷基;或者R.sub.1和R.sub.2一起是Y,其中Y是有一个垂吊的##STR3##的4至8个碳原子的直链或支链烷基,通过首先将α,β-不饱和醛或酮与烷基
膦酸酯反应形成
膦酸酯醛或酮,然后进行经典的Bucherer杂环化合成制备。