Acid-catalysed intramolecular C-alkylation in βγ-unsaturated diazomethyl ketones. A new synthetic route to angularly fused cyclobutanones, bridged cyclopentanones, and γ-lactones
作者:Usha Ranjan Ghatak、Baijayanti Sanyal、Gutta O. S. V. Satyanarayana、Subrata Ghosh
DOI:10.1039/p19810001203
日期:——
Acid-induced decomposition of rigid polycyclic βγ-unsaturated diazomethyl ketones (2a and b) and (4a and b) is shown to give, in excellent yields, the respective angularly fused unsaturated cyclobutanones (5a and b) and (6a and b) and/or the rearranged bridged hydroxycyclopentanones (7a) and (9a) depending upon the reagents, reaction conditions, and the nature of the substrates. Under certain conditions
刚性多环的酸诱导分解β γ不饱和酮重氮(2a和b)和(4a和4b)示出得到,以优良产率,相应的成角度的不饱和稠合cyclobutanones(5a和b)和(6a和6b)和/或重排的桥连的羟基环戊酮(7a)和(9a)取决于试剂,反应条件和底物的性质。在某些条件下,(5a)和(7a)发生重排为3a-甲基-1,2,3,3a,6,7-六氢戊烯[1,6a - a ]萘-4-酮(12a)。不饱和环丁酮经历立体选择性催化加氢成相应的反式角取代的氢菲和氢芴环丁酮(13a和b)和(14a和b),它们在容易的Bayer-Villiger氧化作用下产生γ-内酯(18a和b)和(19a和b)。不饱和环丁酮(5a和b )在用碱性过氧化氢氧化时也提供相应的γ-内酯(20a和b)。