ABSTRACT A facile carbon–sulfur bond formation was observed through the cellulose sulfonic acid (CSA) catalyzed dithioacetal protection of carbonyl compounds. In a preliminary study, the synthesis and characterization of functionalized bio-polymer, cellulose sulphonic acid (CSA) was achieved and its catalytic knack for dithioacetal protection was studied. It was discovered that CSA is an efficient, environmentally benign, recyclable catalyst for the synthesis of 1,1-dithioacetals or 1,1-dithioketals. A diverse range of aldehydes or ketones smoothly underwent the thioacetalization either with 1,3-dithiol or 1,2-dithiol. The 1,3-dithiol protection was found favored over 1,2-dithiol in terms of yields and reaction times. Acetonitrile at room temperature provides the best results among the solvents studied. The biodegradable nature of CSA, operationally simple protocol, good to excellent yields, shorter reaction times and need of very small amount of catalyst are the salient features of the present protocol. GRAPHICAL ABSTRACT

中文翻译：

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通过纤维素磺酸（CSA）催化羰基化合物的二硫缩醛保护探索了一种方便的碳硫键形成

摘要 通过纤维素磺酸 (CSA) 催化的羰基化合物的二硫缩醛保护，观察到一个容易的碳硫键形成。在初步研究中，实现了功能化生物聚合物纤维素磺酸 (CSA) 的合成和表征，并研究了其对二硫缩醛保护的催化诀窍。发现 CSA 是一种高效、环境友好、可回收的催化剂，用于合成 1,1-二硫代缩醛或 1,1-二硫代缩酮。各种醛或酮可以顺利地与 1,3-二硫醇或 1,2-二硫醇进行硫缩醛化。发现就产率和反应时间而言，1,3-二硫醇保护优于 1,2-二硫醇。在所研究的溶剂中，室温下的乙腈可提供最佳结果。CSA 的可生物降解性质，操作简单的协议、良好的收率、更短的反应时间和需要非常少量的催化剂是本协议的显着特点。图形概要