Odorless 2-(1,3-dithian-2-ylidene)-3-oxobutanoic acid (1c) was prepared and investigated in the thioacetalization of carbonyl compounds as a 1,3-propanedithiol equivalent. The results showed that the thioacetalization of various carbonyl compounds 2 with 1c proceeded smoothly and afforded the corresponding dithioacetals 3 in high yields (up to 99%) in the presence of acetyl chloride at room or reflux temperatures. Moreover, the thioacetalization exhibited high chemoselectivity between aldehydes and ketones. Key words: chemoselectivity, 2-(1,3-dithian-2-ylidene)-3-oxobutanoic acid, α-oxo ketene dithioacetal, 1,3-propanedithiol equivalent, thioacetalization.

中文翻译：

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用无味的 2-(1,3-dithian-2-ylidene)-3-oxobutanoic 酸作为 1,3-丙二硫醇等价物的化学选择性硫缩醛化

制备了无味的 2-(1,3-dithian-2-ylidene)-3-氧代丁酸 (1c)，并在羰基化合物的硫代缩醛反应中作为 1,3-丙二硫醇等价物进行了研究。结果表明，在乙酰氯的存在下，在室温或回流温度下，各种羰基化合物 2 与 1c 的硫代缩醛化反应顺利进行，并以高产率（高达 99%）得到相应的二硫代缩醛 3。此外，硫缩醛化在醛和酮之间表现出高化学选择性。关键词: 化学选择性, 2-(1,3-dithian-2-ylidene)-3-oxobutanoic acid, α-oxo ketene dithioacetal, 1,3-propanedithiol 等价物, thioacetalization。