corresponding alkenes have been hydrogenated over heterogeneous palladium or platinum catalysts to give medium and large heterocycles either resulting from direct cyclisation or by the formation of dimers. The yields of monomers and dimers are discussed as a function of ring size and the pattern of heteroatom substitution in the substrates; in general the greater the number of heteroatoms in the chain
可以通过相应的烯烃的加氢甲酰化而容易获得的各种带有含醛侧链的硝基
芳烃,已在非均相
钯或
铂催化剂上氢化,以产生中环和大环,这些环是由直接环化或通过形成二聚体而产生的。讨论了单体和二聚体的产率与环大小和底物中杂原子取代模式的关系。通常,链中杂原子的数目越多,环状化合物的产率就越高。