Ethyl diazoacetate → ethyl 5-methoxy-1a,2,3,7b-tetrahydro-1H-cyclopropa[a]naphthalene-1-carboxylate

Participants

Reaction Steps

7-Methoxy-1,2-dihydronaphthalene (8.8 g, 0.055 mol) was mixed with 1 ml of degassed absolute methylene chloride and 20 mg of rhodium acetate (appr. 0.1 mol %). The reaction mixture was bubbled with nitrogen and ethyl diazoacetate (2 eq, 50% solution in degassed abs. methylene chloride) was added slowly through the syringe (flow rate about 1 ml/hour) to the stirred solution at ambient temperature. Gas evolution started upon the addition. The reaction was monitored by GC. Additional amount of catalyst was added during the reaction (about 20 mg). GC-ratio of cis/trans isomers was 21:48.

Provenance & Evidence