Reactions of organo-metal compounds O 0350Reformatsky Reaction of Methyl 1-Bromocycloalkanecarboxylates with α-Dicarbonyl Compounds. -The Reformatsky reaction of carboxylates (II) with oxoacetaldehydes (I) proceeds at both carbonyl groups of (I). It is accompanied by a double intramolecular cyclization leading to the fused spiro bis-lactones (III). Oxoacetaldehyde (IV) reacts with (II) only at the aldehyde carbonyl group due to the steric hindrance of the ortho-methyl substituent. The reaction of compounds (II) with dibenzoyl (VI) proceeds at both carbonyl groups; however, the second intramolecular cyclization step is hindered. -(KIRILLOV, N. F.; SHCHEPIN, V. V.; VEDERNIKOVA, L. A.; Russ. J. Org. Chem. 40 (2004) 7, 953-956; Dep. Chem., Perm State Univ., Perm 614990, Russia; Eng.) -R. Staver 09-047