Ethyl tetrolate

Ethyl tetrolate Tetrolic acid, ethyl ester (8) 2-Butynoic acid, ethyl ester (9) (4341-76-8)... 

Benzoyl-1,2-dihydro-1-cyanoisoquinoline was treated with fluoro-boric acid in glacial acetic acid to give the Reissert salt 56 reactions of the latter with EPP, DMAD, and ethyl tetrolate were examined. With EPP, the initial bridged compound 58 was isolated as a moderately stable crystalline compound, and was the first example of an isolated... 

Factors influencing orientation in the condensation of 57 with dipolarophiles were examined by employing ethyl tetrolate in place of the phenylpropiolate. A clean reaction was not obtained, but eventually 60 was isolated indicating that the sterically less demanding ester still adds in the same manner. 

Methyl derivatives of 2-oxo-2//-pyrido[l,2-a]pyrimidines were prepared by Kato et al.19 and Potts et al.2 by using 2-bromocrotonic acid and ethyl tetrolate, respectively. 

The present procedure illustrates the simplest convenient method for the preparation of (Z)- or (E)-y-iodo allylic alcohols and (Z)-p-iodoacrolein. It uses ethyl propiolate as a unique starting material ethyl propiolate and ethyl tetrolate can be hydroiodinated regio- and stereospecifically (Z > 99%) by reaction with inexpensive sodium iodide in acetic acid3 (Scheme 1). The same methodology has been applied... 

The organometallic reagent (1) reacts with ethyl tetrolate in the sequence above to give ethyl / , -dimcthylacrylate (7),... 

The requisite functionalized monomer 5 was prepared by the atation of the published syndiesis of HMDB (5-5). First, 2-butyne was dimerized in the presence of aluminum chloride and treated in situ with ethyl tetrolate to provide ethyl pentamethyl Dewar benzoate. (3). Reduction of 3 with diisobutyl aluminum hydride produced the alcohol 4, which was esterified with methacryloyl chloride to generate monomer 5. The desired copolymers of 5 with various methacrylic esters were synthesized by solution polymerization using an azo initiator, yielding the 10/90 copolymers 6. 

Other Reactions. Other substrates that have been found to react with silyl-copper reagents and with silyl cuprates are allyl chlorides, an alkyl bromide, epoxides, acid chlorides, propargyl acetates and sulfides, a vinyl iodide, an amino-methyl acetate, ethyl tetrolate, and some strained allylic ethers. ... 

The esters of acetylenic acids, with the exception of a,/3-unsatiU ated acids, can be converted to hydrazides. Ethyl stearolate and ethyl undecynoate readily give hydrazides, the latter in 80% yield. Esters of a,/3-acetylenic acids react with hydrazine to form pyrazolones for example, ethyl tetrolate gives 3-methyl-5-pyrazolone. ... 

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