A series of chloroalkynes activated with extremely strong electron withdrawing polyfluoroalkyloxalyl substituents were prepared for the first time from available bis(trimethylstannyl) acetylene and the corresponding acid chlorides. Hexafluoroisopropyl ester, thus obtained, probably proved to be the most electrophilic alkyne known so far. It is not only extremely strong dienophile in the Diels-Alder reaction, but undergoes the unusual uncatalyzed [2+2]-cycloaddition reactions with simple alkenes under very mild conditions.

中文翻译：

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4-氯-2-氧代丁-3-炔酸的多氟酯。六氟异丙基4-氯-2-氧代丁-3-炔酸酯的环加成反应反应

首次从可得的双（三甲基锡烷基）乙炔和相应的酰氯中制备了一系列用极强的吸电子多氟烷基草酰取代基活化的氯炔烃。由此获得的六氟异丙基酯可能被证明是迄今为止已知的最亲电子的炔烃。它不仅在Diels-Alder反应中具有极强的亲二烯性，而且在非常温和的条件下与简单的烯烃发生异常的未催化的[2 + 2]-环加成反应。