Ethoxy- l- trimethylsilyloxy cyclopropane

Another approach to the synthesis of the parent compounds involves the reaction of 1-ethoxy-l-trimethylsilyloxy cyclopropane prepared according to the Rhhlman method and selenols, in the presence of zinc chloride (Scheme 31a). The reaction is quite rapid with methylselenol but much more difficult with phenylselenol It takes a completely different course when an alkyl substituent is present on the cyclopropane ring Surprisingly thus methylselenol cleaves the cyclopropane ring of 1-ethoxy-1-trimethylsilyloxy-2-ethyl cyclopropane on addition of zinc chloride and lead to l,l-bis(methylseleno)pentane by reductive selenoacetalisation (Scheme 31 b). 

The 1-Ethoxy-l-(trimethylsilyloxy)cyclopropane is widely used in various reactions. Cyclization of optically pure /3-halo esters gives cyclopropanone acetals enantiomerically pure at C-2 and a 1 1 diastereomeric mixture at C-1 (eq 17). ... 

Homo-Reformatsky reaction.1 The reaction of 1-ethoxy-1-trimethylsilyloxy-cyclopropane (1) with an aldehyde in the presence of ZnCl2 results in y-silyloxy esters via a zinc homoenolate (a) of ethyl propionate (equation I). Znl2 is the preferred catalyst in the case of reactions with acetophenone and benzaldehyde dimethyl acetal and in reactions of l-isopropoxy-l-(t-butyldimethylsilyl-oxy)cyclopropane with aromatic aldehydes. 

Cyclopentanes, synthesis, 66, 10 CYCLOPENTANONE SYNTHESIS, 66, 87, 92, 93 Cyclopentanone, 2-carbomethoxy-3-vinyl, 66, 56 Cyclopentanone, 2-ethenyl-2-methyl (88729-76-4), 66, 94 2-CYCL0PENTEN-1 -ONE, 3-METHYL-2-PENTYL-, 65, 26 Cyclopropane, 1-trimethylsilyloxy-l-ethoxy-, 66, 44 Cyclopropanecarboxylic acid chloride, 66, 176... 

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