Cyclopropanone ketals cyclopropanes

Cyclopropanecaiboxylic acid, 56, 70 Cyclopropanes, em-dihalo, 56, 32 Cyclopropanone ketals, 58, 40 Cyclopropenes, 58, 40 CYCLOPROPENONE, 57, 41 CYCLOUNDECANONE, 56, 107 Cycloundecanone, 2-hydroxy-, 56, 110 Cycloundecene, 1-caiboxy-, 56, 111 Cycloundecene, 1-methoxy-, 56, 111 1-Cycloundecene-l-carboxylic acid, methyl ester, 56, 108... 

Recently it has been shown that cyclopropanone ketals and hemiketals can be prepared conveniently by cyclopropanation of ketene alkylsilyl ketals or ketene disilyl ketals with diethylzinc-methylene iodide in ether ... 

Cyclopropanes, 101, 267 Cyclopropanone ketals, 315-316 Cyclopropene, 113 Cyclopropenone, 519 Cyclopropenones, 27, 399 Cyclopropylacetylene, 401 Cyclopropyl azides, 323 Cyclopropylcarbinyl compounds, 53 Cyclopropyldiphenylsulfonium fluoroborate, 211,213-214... 

Use of the Simmons-Smith reagent for the formation of cyclopropanone precursors has been reported in the case of ethoxy vinyl carboxylates (1) and ketene ketals (2) (Scheme 2). Using 1-ethoxyvinyl acetate and benzoate, it was found that the zinc iodide generated in the reaction tends to favor opening of the cyclopropane ring. However use of glyme as a solvent prevents attack on the ring by this Lewis acid since the zinc salt is insoluble in that medium . 

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