- Synthesis of densely substituted 1,3-butadienes through acid-catalyzed alkenylations of α-oxoketene dithioacetals with aldehydes
-
Aldehydes were proved to be viable reagents for implementing alkenylation of α-oxoketene dithioacetals. AlCl3 was found to be the best catalyst. The established reaction opened an avenue to access densely substituted 1,3-butadiene derivatives. The obtained product bears multiple reactive sites that can be converted into various valuable molecules. (Chemical Equation Presented).
- Liu, Changhui,Gu, Yanlong
-
p. 9619 - 9627
(2015/01/09)
-
- Copper-catalyzed trifluoromethylation of internal olefinic C-H bonds: Efficient routes to trifluoromethylated tetrasubstituted olefins and N-heterocycles
-
The functionalization of internal olefins has been a challenging task in organic synthesis. Efficient CuII-catalyzed trifluoromethylation of internal olefins, that is, α-oxoketene dithioacetals, has been achieved by using Cu(OH)2 as a catalyst and TMSCF3 as a trifluoromethylating reagent. The push-pull effect from the polarized olefin substrates facilitates the internal olefinic C-H trifluoromethylation. Cyclic and acyclic dithioalkyl α-oxoketene acetals were used as the substrates and various substituents were tolerated. The internal olefinic C-H bond cleavage was not involved in the rate-determining step, and a mechanism that involves radicals is proposed based on a TEMPO-quenching experiment of the trifluoromethylation reaction. Further derivatization of the resultant CF 3 olefins led to multifunctionalized tetrasubstituted CF3 olefins and trifluoromethylated N-heterocycles.
- Mao, Zhifeng,Huang, Fei,Yu, Haifeng,Chen, Jiping,Yu, Zhengkun,Xu, Zhaoqing
-
supporting information
p. 3439 - 3445
(2014/04/03)
-
- Iron-catalyzed alkylation of α-oxo ketene dithioacetals
-
Iron-catalyzed alkylation of internal olefins, that is, α-oxo ketene dithioacetals, was successfully realized by using styrenes as the alkylating reagents. Highly functionalized tetrasubstituted olefins were prepared in moderate to high yields. the Partner Organisations 2014.
- Yang, Qin,Wu, Ping,Chen, Jiping,Yu, Zhengkun
-
supporting information
p. 6337 - 6339
(2014/06/09)
-
- Oxidative cross-esterification of dithiolanes with alcohols through a cross-dehydrogenative coupling (CDC)/deprotection sequence
-
An unprecedented oxidative cross-esterification in an equimolar mixture of dithiolanes, alcohols and water through a CDC/deprotection sequence has been developed. The reaction itself features simple experimental procedures under very mild conditions and offers a new strategic protocol for the direct and efficient synthesis of structurally diverse esters.
- Fu, Liang,Yao, Chang-Jiang,Chang, Ning-Jie,Chen, Jia-Rong,Lu, Liang-Qiu,Xiao, Wen-Jing
-
p. 506 - 508
(2012/01/15)
-
- Unexpected hydrobromic acid-catalyzed C-C bond-forming reactions and facile synthesis of coumarins and benzofurans based on ketene dithioacetals
-
Hydrobromic acid was found to be a unique catalyst in C-C bond-forming reactions with ketene dithioacetals. Distinctly different from other acids (including Lewis and Bronsted acids), the remarkable catalytic performance of hydrobromic acid in catalytic a
- Yuan, Hongjuan,Wang, Mang,Liu, Yingjie,Wang, Lili,Liu, Jun,Liu, Qun
-
experimental part
p. 13450 - 13457
(2011/02/27)
-
- Unexpected Formation of Benzaldehydes by the Reactions of Dithio- Acetals Derived from Cinnamaldehydes with 2,3-Dichloro-5,6-dicyano-p-benzoquinone in Aqueous Solvents
-
1,3-Dithianes 1, 1,3-dithiolanes 2, and diphenyl dithioacetals 3 derived from cinnamaldehydes reacted with 2,3-dichloro-5,6-dicyano-p-benzoquinone in aqueous solvents to give benzaldebydes 4. Hydride transfer from 1-3 to 2,3-dichloro-5,6-dicyano-p-benzoquinone followed by hydrolysis and oxidative carbon-carbon bond cleavage would produce benzaldehydes 4.
- Tanemura, Kiyoshi,Nishida, Yoko,Suzuki, Tsuneo,Satsumabayashi, Koko,Horaguchi, Takaaki
-
p. 457 - 460
(2007/10/03)
-
- Oxidative removal of 1,3-dithiane protecting groups by 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ)
-
A number of 1,3-dithianes have been efficiently converted into the parent carbonyl compounds in good yields by treatment with 1.5 equiv. of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) in MeCN-H2O (9:1). The reactions of 2-aryl-substituted 1,3-dithianes bearing electron-donating groups on the benzene ring with DDQ afforded thioesters along with aldehydes. 1,3-Dithiolanes derived from aromatic aldehydes were transformed to thioesters, whereas 1,3-dithiolanes derived from aliphatic and aromatic ketones were stable under these reaction conditions. Diphenyl dithioacetals were stable except for 4-methoxy- and 3,4-dimethoxy-benzaldehyde diphenyl dithioacetals which gave the corresponding aldehydes. Selective cleavage reactions of 1,3-dithiane in the presence of 1,3-dithiolane or diphenyl dithioacetal have been investigated.
- Tanemura, Kiyoshi,Dohya, Hiroshi,Imamura, Masanori,Suzuki, Tsuneo,Horaguchi, Takaaki
-
p. 453 - 457
(2007/10/03)
-
- A convenient one-pot synthesis of ketene dithioacetals
-
An easy synthesis of ketene dithioacetals 2 and 3 by the condensation of carbon disulfide and active methylene compounds 1 with subsequent alkylation in the presence of potassium fluoride is described.
- Villemin,Alloum
-
p. 301 - 303
(2007/10/02)
-