Two efficient synthetic methods for preparation of 3-(trifluoromethyl)cyclobutane-1-carboxylic acid are reported starting from readily available 4-oxocyclobutane precursors. These cyclobutanones can be converted to their CF₃ carbinols upon treatment with TMSCF₃ and a fluoride source. The bis-carboxylate system 9 was deoxygenated by treatment of Bu₃SnH and provided desired compound 1 upon decarboxylation. In the monocarboxylate system 15, the triflate could be efficiently eliminated; subsequent hydrogenation afforded cis-1.

中文翻译：

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3-（三氟甲基）环丁烷-1-羧酸的两个可扩展合成

从容易获得的4-氧代环丁烷前体开始，报道了两种用于制备3-（三氟甲基）环丁烷-1-羧酸的有效合成方法。这些环丁酮可以在用TMSCF ₃和氟化物源处理后转化为CF ₃甲醇。通过Bu ₃ SnH的处理使双羧酸酯体系9脱氧，并在脱羧后提供所需的化合物1。在单羧酸盐体系15中，可以有效地消除三氟甲磺酸盐；随后的氢化，得到顺式- 1。