P,y-Ethylenecarboxylic acid esters

E)-P,y-ethylenecarboxylic acid esters from acoxy-2-ethylenes 44, 722... 

A soln. of p-nitrobenzyl benzyloxycarbonyl-L-phenylalanyl-Nim.piperidinocarbo-nyl-L-histidylglycinate in abs. ethanol-dimethylacetamide allowed to react 15 hrs. at room temp, with 5 moles 100%-hydrazine hydrate -> benzyloxycarbonyl-L-phenylalanyl-L-histidylglycine hydrazide. Y 95%. F. e., also removal with NaOH, s. G. Jager, R. Geiger, and W. Siedel, B. 101, 3537 (1968) a,y -ethylenecarboxylic acid hydrazides from active esters s. R. Harada and H. Kondo, Bull. Chem. Soc. Japan 41, 2521 (1968). 

E)-y,5-ethylenecarboxylic acid esters from oxo compds. 44, 192 P,y-ethyleneketones from oxo compds. 43, 713... 

A soln. of 5.0 g. ethyl 8/, 8a/ -dimethyl-l-oxo-l,2,3,4,6,7,8,8a-octahydro-2-naph-thoate in hexamethylphosphoramide added at 5° under Ng to a stirred mixture of a 60%-dispersion ofNaHin mineral oil and hexamethylphosphoramide, stirring continued 1 hr. at room temp., cooled to 5°, 1.93 g. chloromethyl methyl ether added, and stirred 2 hrs. at room temp. 5.7 g. crude methoxymethyl enol ether dissolved in ether, added rapidly with Dry Ice-cooling under argon to a stirred dark blue soln. of Li in anhydrous NH3, and stirring continued 12 min. at -33°, the b. p. of liq. NHg 2.85 g. ethyl 8/, 8ai -dimethyl-l,2,3,4,6,7,8,8a-octahydro-2j -naphthoate. Overall Y 60%. - 0-Alkylation of the startg. -keto esters occurs under the above conditions to the complete exclusion of the C-alkylated isomer. The subsequent reduction gives the less stable axial isomer. R. M. Coates and J. E. Shaw, J. Org. Chem. 35, 2597 (1970) f. e. s. ibid. 35, 2601 carboxylic acids, also from a,/ -ethylenecarboxylic acids, cf. ibid. 36, 1151 (1971). 

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