| Abstract
| - The sodium salt of dimethyl 1,3-acetonedicarboxylate(1) readily reacts with certain alkynals undermild conditions in THF to give a tetrasubstituted aromatic ring withregiocontrol at the meta-position through a Michael addition−aldol cyclization sequence.Thus the reaction of I withpropynal, 2-butynal, 2-pentynal, 2-octynal, 4-(benzoyloxy)-2-butynal,and 4-((tetrahydropyranyl)oxy)-2-butynal at 25 °C gave the following products: dimethyl2-hydroxybenzene-1,3-dicarboxylate(11%), dimethyl 2-hydroxy-4-methylbenzene-1,3-dicarboxylate (45%),dimethyl 4-ethyl-2-hydroxybenzene-1,3-dicarboxylate (46%), dimethyl2-hydroxy-4-pentylbenzene-1,3-dicarboxylate (42%),dimethyl2-hydroxy-4-((pivaloyloxy)methyl)benzene-1,3-dicarboxylate(88%), dimethyl 2-hydroxy-4-((benzoyloxy)methyl)benzene-1,3-dicarboxylate (74%), anddimethyl 2-hydroxy-4-(((tetrahydropyranyl)oxy)methyl)benzene-1,3-dicarboxylate(70%).
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