作者:A.L. Kurts、N.K. Genkina、A. Macias、L.P. Beletskaya、O.A. Reutov
DOI:10.1016/s0040-4020(01)98183-9
日期:1971.1
Effect of the alkylating agent nature in the case of O- and C-alkylation of both ethyl acetoacetate and acetylacetonate anions is reported. The value of the O/C-ratio depends on three factors: the polar effect of the alkyl substituents in the alkylating agents, the steric effect of the alkyl groups and the symbiotic effect of the leaving groups. The relative contributions of the first two effects depends
据报道,在乙酰乙酸乙酯和乙酰丙酮阴离子的O-和C-烷基化的情况下,烷基化剂性质的影响。O / C比的值取决于三个因素:烷基化剂中烷基取代基的极性效应,烷基的空间效应和离去基团的共生效应。前两种效应的相对贡献取决于离去基团的性质。当离去基团为软碱(碘化物,溴化物,氯化物)且O / C比以秒为单位降低时,空间效应占主导地位。Bu> iPr> Et> Me。硬离去基团甲苯磺酸酯的情况与上述给定顺序相反的烷基顺序与烷基硬度的皮尔逊顺序相反。还报道了离去基团性质对O / C比的影响。发现离去基团对两种烯醇离子的甲基化都有很强的共生作用。在乙基化中,离去基团的作用较难检测到。对于两个仲烷基,O / C比对离去基团的性质几乎不敏感。