22914-06-3Relevant articles and documents
TITANIUM TETRACHLORIDE, AN EFFICIENT AND CONVENIENT REAGENT FOR THIOACETALIZATION
Kumar, Vijay,Dev, Sukh
, p. 1289 - 1292 (1983)
Aldehydes and ketones, when exposed to alkyl thiols or suitable alkane dithiols in presence of titanium tetrachloride, furnish near quantitative yields of the corresponding thioacetals.
Silica-supported phosphorus pentoxide: A reusable catalyst for S,S-acetalization of carbonyl groups under ambient conditions
Shaterian, Hamid Reza,Azizi, Kobra,Fahimi, Nafiseh
experimental part, p. 85 - 91 (2012/01/06)
Phosphorus pentoxide supported on silica gel (P2O 5/SiO2) efficiently acts as a highly active and reusable catalyst for cyclic and non-cyclic S,S-acetalization of a variety of carbonyl compounds under mild, solvent-free an
Chemoselective (trans)thioacetalization of carbonyl compounds with a reusable lewis acid-surfactant-combined copper bis(dodecyl sulfate) catalyst in water
Weng, Shiue-Shien,Chang, Shen-Chun,Chang, Tsuan-Hao,Chyn, Jong-Pyng,Lee, Shu-Wei,Lin, Chao-An,Chen, Fong-Kuang
experimental part, p. 1493 - 1499 (2010/10/03)
A Lewis acid-surfactant-combined copper bis(dodecyl sulfate) [Cu(DS) 2] catalyst served as an efficient and reusable catalyst for the thioacetalization and transthioacetalization of carbonyl compounds and O,O-acetals in water at room temperature. Some of the major advantages of this procedure are high chemoselectivity, ease of operation and purification without any organic solvent, and high yields. Georg Thieme Verlag Stuttgart.
Catalytic carbon-sulfur bond formation by amphoteric vanadyl triflate: exploring with thia-Michael addition, thioacetalization, and transthioacetalization reactions
Chen, Chien-Tien,Lin, Yow-Dzer,Liu, Cheng-Yuan
supporting information; experimental part, p. 10470 - 10476 (2010/02/28)
A series of thiols have been examined as protic nucleophiles for Michael-type additions to α,β-unsaturated carbonyls as well as double nucleophilic condensations with aldehydes, ketones, and acetals catalyzed by amphoteric, water-tolerant vanadyl triflate under mild and neutral conditions. The newly developed C-S bond formation protocols were carried out smoothly in good to high yields in a highly chemoselective manner.
Hafnium trifluoromethanesulfonate (hafnium triflate) as a highly efficient catalyst for chemoselective thioacetalization and transthioacetalization of carbonyl compounds
Wu, Yan-Chao,Zhu, Jieping
supporting information; experimental part, p. 9522 - 9524 (2009/04/06)
(Chemical Equation Presented) A range of carbonyl compounds including aliphatic and aromatic aldehydes and ketones were converted to the corresponding thioacetals in high yields in the presence of a catalytic amount of hafnium trifluoromethanesulfonate (0.1 mol %, room temperature). The mild conditions tolerated various sensitive functional and protecting groups and were racemization-free when applied to α-aminoaldehydes. Transacetalization and chemoselective thioacetalization of aromatic aldehydes in the presence of aliphatic aldehydes and ketones were also documented.
GaCI3- and TiCl4-catalyzed insertion of isocyanides into a C-S bond of dithioacetals
Tobisu, Mamoru,Ito, Sana,Kitajima, Aki,Chatani, Naoto
supporting information; body text, p. 5223 - 5225 (2009/06/18)
(Chemical Equation Presented) The insertion reaction of isocyanide into a C-S bond of dithioacetals is catalyzed by GaCl3 or TiCl4 to afford thioimidates containing an a-alkylthio group. Balanced thiophilicity of these Lewis acids is
Simple, mild and efficient thioacetalization and transthioacetalization of carbonyl compounds and deprotection of thioacetals: Unique role of thiols in the selectivity of thioacetalization
Das, Biswanath,Ramu, Ravirala,Reddy, Majjigapu Ravinder,Mahender, Gurram
, p. 250 - 254 (2007/10/03)
Silica supported sodium hydrogen sulfate (NaHSO4·SiO 2) has been employed for efficient thioacetalization and transthioacetalization of carbonyl compounds in CH2Cl2 at room temperature. Selectivity of thioacetalization was dependent on the thiols used for the conversion. The same catalyst was also found to be effective for deprotection of thioacetals in CH2Cl2-H2O at room temperature.
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
Iranpoor, Nasser,Firouzabadi, Habib,Shaterian, Hamid Reza,Zolfigol
, p. 1047 - 1071 (2007/10/03)
The use of 2,4,4,6-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 yields in the presence of thiols.
An expeditious synthesis of dithioacetals using zeolites
Kumar,Reddy,Singh,Pandey
, p. 67 - 69 (2007/10/02)
A simple and efficient catalytic method for dithioacetalization of various carbonyl compounds (saturated and α,β-unsaturated aliphatic, aromatic, heteroaromatic and hindered) with ethanethiol and 1,3-propanedithiol using H-Y and H-mordenite (H-M) zeolites
Hard Acid and Soft Nucleophile Systems. Part 11. Har-Soft Affinity Inversion: Dehalogenation of α-Halogeno Ketones with Aluminium Chloride and a Thiol
Fuji, Kaoru,Node, Manabu,Kawabata, Takeo,Fujimoto, Mayumi
, p. 1043 - 1048 (2007/10/02)
α-Halogeno ketones have been dehalogenated with a combination of aluminium chloride and ethanethiol.The mechanism involved in deiodination and debromination differs from that of dechlorination and defluorination.A hard-hard interaction between carbonyl oxygen and aluminium chloride and a soft-soft interaction between iodine or bromine and thiol are the dominant factors for direct deiodination and debromination.In dechlorination and defluorination there is initial formation of the corresponding dithioacetal, whereby hard carbonyl oxygen is replaced by the soft sulphur atom. α-Chloro- and α-fluoro-dithioacetals then undergo dehalogenation to afford vinyl sulphide as a result both of a favourable soft-soft interaction between the sulphur atoms in the dithioacetal entity and thiol, and also a favourable hard-hard interaction between the nucleopilic chlorine or fluorine and aluminium chloride. α-Chloro- and α-fluoro-benzyl benzyl ketones afforded the dehalogenated product with concomitant 1,2-transposition of the carbonyl group.This suggests that there is an indirect path which operates competitively via a 1,2-dithio-olefin from α=halogenodithioacetals to vinyl sulphide.Addition of thiol to vinyl sulphide leads to the final product.A concept of hard-soft affinity inversion is proposed.
