Sulfur-Directed Ligand-Free C–H Borylation by Iridium Catalysis
摘要:
An iridium-catalyzed ortho C-H borylation reaction directed by;cyclic dithioacetal moiety is disclosed. A series of borylation products were obtained in moderate to good yields under mild conditions in exclusive mono- and ortho-regioselectivity. Thus, the 1,3-dithiane or 1,3-dithiolane group serves as a remarkable effective directing group for C-H borylation without any ligand assistance. The further transformations of the borylation products are also carried out to change boryl group to other functional groups.
2,4,4,6-Tetrabromo-2,5-cyclohexadienone (TABCO), N-Bromosuccinimide (NBS) and Bromine as Efficient Catalysts for Dithioacetalization and Oxathioacetalization of Carbonyl Compounds and Transdithioacetalization Reactions
作者:Nasser Iranpoor、Habib Firouzabadi、Hamid Reza Shaterian、M. A. Zolfigol
DOI:10.1080/10426500211712
日期:2002.5.1
6-tetrabromo-2,5-cyclohexadienone (TABCO), N-bromosuccinimide (NBS), and bromine as efficient catalysts for conversion of carbonyl compounds to their cyclic and acyclic dithioacetals and 1,3-oxathiolanes under mild reaction conditions are described. These catalysts are also used for efficient transdithioacetalization of acetals, diacetals, ketals, acylals, enamines, hydrazones, and oximes with high
2,6-Dicarboxypyridinium Chlorochromate. An Efficient and Selective Reagent for the Mild Deprotection of Acetals, Thioacetals, and 1,1-Diacetates to Carbonyl Compounds
chlorochromate (2,6- DCPCC ) was found to be an efficientreagent for the conversion of acetals, thioacetals, and 1,1-diacetates to their corresponding carbonyl compounds under neutral and anhydrous conditions in good to excellent yields. Selectivedeprotection of acetals or 1,1-diacetates in the presence of thioacetals at room temperature is also observed with this reagent.
SBA-15 functionalized sulfonic acid containing a confined hydrophobic and acidic ionic liquid: a highly efficient catalyst for solvent-free thioacetalization of carbonyl compounds at room temperature
作者:Babak Karimi、Majid Vafaeezadeh
DOI:10.1039/c3ra42286k
日期:——
SBA-15 functionalized sulfonic acid containing a confined ionic liquid has been introduced to convert various carbonylcompounds to their corresponding dithioacetals and dithioketals at room temperature and under solvent-free conditions. It was found that coating SBA-15-Pr-SO3H with the hydrophobic and acidic ionic liquid [OMIm]HSO4 at a loading of 0.8 mL g−1 of silica, afforded paths for faster mass transfer
引入了一种含有受限离子液体的SBA-15官能化磺酸的新应用,可在室温和无溶剂条件下将各种羰基化合物转化为其相应的二硫缩醛和二硫缩酮。发现以0.8 mL g -1的二氧化硅负载疏水性和酸性离子液体[OMIm] HSO 4涂覆SBA-15-Pr-SO 3 H ,提供了将原料更快地质量转移到SBA-15-Pr-SO 3 H中的途径。活动站点。同时,由于酸性位点的协同作用机理,它也可能增加布朗斯台德酸的强度。催化剂可以很容易地回收和再利用至少八个反应循环,而其催化活性只有轻微的损失。
Aluminum hydrogen sulfate [Al(HSO4)3] as an efficient catalyst for the preparation of thioacetals
作者:Majid Ghashang
DOI:10.1007/s11164-012-0802-8
日期:2013.7
Aluminum hydrogen sulfate, as a heterogeneous solid acid catalyst, has been used for the mild conversion of carbonyl compounds to their thioacetals using 1,2- and 1,3-dithiol under ambient conditions with short reaction times in high to excellent yield in acetonitrile as solvent.
An expedient carbon–sulfur bond formation explored through the cellulose sulfonic acid (CSA) catalyzed dithioacetal protection of carbonyl compounds
作者:Kailas R. Kadam
DOI:10.1080/17415993.2020.1775835
日期:2020.9.2
facile carbon–sulfur bond formation was observed through the cellulose sulfonicacid (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