
%0 Journal Article
%A Collins, DJ 
%A Downes, LM 
%A Kyriakou, M 
%T Enolic Ortho Esters. III. Preparation of a Keto Acetal by Hydride Reduction of an Enolic Ortho Ester
%J Australian Journal of Chemistry
%D 1989/09/01
%V 42
%N 9
%P 1617-1622
%K 
%R https://doi.org/10.1071/CH9891617
%U https://www.publish.csiro.au/paper/CH9891617 
%X Lithium aluminium hydride reduction of the enolic ortho ester 4&#8242;,4&#8242;-dimethyl-3,4,5,8-tetra-hydrospiro [2H-l-benzopyran-2,21-[1,3]dioxolan] (8) in the absence of solvent gave 6-[21-(4&#8243;,4&#8243;- dimethyl-1&#8243;,3&#8243;-dioxolan-2&#8243;-yl)ethyl]cyclohex-3-en-1-one (11) which was isomerized to the &#945;'&#946;-unsaturated keto acetal (10). Similarly, hydride reduction of the phenolic ortho ester 4&#8242;-methyl-3,4-dihydrospiro[2H-1-benzopyran-2,2&#8242;-[1,3]dioxolan] (12a) and the 4&#8242;,4&#8242;-dimethyl analogue (12b), afforded the corresponding phenolic acetals (14a) and (14b) respectively, in high yields.&#8242; 
