Oeo. Hormi et Am. Moilanen, EXPERIMENTAL STUDIES OF LEWIS-ACID CATALYZED ADDITIONS OF LONG CHAINED ALCOHOLS TO ACTIVATED 1,4-BENZOQUINONE, Tetrahedron, 54(9), 1998, pp. 1943-1952
Lewis acid promoted additions of long chained alcohols to 2-carbometho
xy-1,4-benzoquinone (1) have been examined by using various LAs; AlCl3
, TiCl4, MgBr2 and MgCl2. It has been found that the bidentate Lewis a
cid MgCl2, having ability to coordinate to both carbonyl oxygens (chel
ate control) of 2-carbomethoxy-1,4-benzoquinone (1), produced the addi
tion product almost quantitatively at mild conditions. The MgCl2 catal
yzed additions of alcohols have been utilized in the synthesis of rare
2-alkoxyhydroquinones (7a-e). The reactions between quinone 1, alcoho
l and AlCl3 or TiCl4 have also been investigated by using NMR spectros
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