Frans-Ethylene derivatives

Acetic anhydride I potassium hydroxide Preferential dehydration of alcohols frans-Ethylene derivatives from alcohols... 

Hydrocarbons from acoxy compounds frans-Ethylene derivatives—Stereospecific synthesis... 

Monoperoxysuccinic acid frans-Glycols from ethylene derivatives s. 19,192... 

Lithium hydride-lithium liq. ammonia frans-Ethylene from acetylene derivatives with retention of hydroxyl groups... 

Dialkoxycarbonylation has been reported using a Pd-catalyst/oxidant system on propynols or butynols furnishing respectively /3- or y-lactone derivatives with a-(alkoxycarbonyl)ethylene chains (Scheme 24) [83,137, 138]. This reaction occurs in a stereospecific way leading exclusively to cis-dicarbonylated products in fair to excellent yields (25-97%). Noteworthy, a butynol bearing an alkyl or an aryl substituent instead of a TMS one undergoes a different course of reaction under the same conditions here frans-alkoxycarbonylation takes place selectively (Scheme 25). 

The derivatives 24 were synthesised by the acylation of trans-2-aminocy-clopentanol (n=l) or frans-2-aminocyclohexanol (n=2) with 3,3-ethylene-dioxydodecanoic acid in the presence of EDC, DMAP and DIPEA followed by acidolysis with THF in DCM. The cycloalkanone analogues 25 were obtained by Swern oxidation of the corresponding cycloalkanols 24 (Scheme 10). 

Non-natural ACC derivatives have been synthesized in order to test their eventual biological activity. Thus, in alkyl-ACC derivatives the alkyl and carboxyl groups must be in trans positions to be metabolized by plant tissue [111a]. For instance, the frans-methyl-ACC 80 serves as a good inhibitor of ethylene... 

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