- Lithium bromide, a novel and highly effective catalyst for monothioacetalization of acetals under mild reaction conditions
-
Lithium bromide is efficient as a catalyst for the monothioacetalization of acetals under mild reaction conditions to provide products in excellent yields with high chemoselectivity.
- Ono,Negoro,Sato
-
p. 1581 - 1583
(2007/10/03)
-
- Polymer-supported dicyanoketene acetal as a π-acid catalyst: Monothioacetalization and carbon-carbon bond formation of acetals
-
Polymeric dicyanoketene acetals (DCKA) were synthesized by copolymerization of styrene and divinylbenzene or ethylene glycol dimethacrylate. These novel polymers could be used successfully as recyclable π-acid catalysts in monothioaCetalization or carbon-carbon bond forming reaction of acetals.
- Tanaka, Nobuyuki,Miura, Tsuyoshi,Masaki, Yukio
-
p. 1010 - 1016
(2007/10/03)
-
- Unprecedented polymer-supported π-acid: Synthesis and its application as a promoter to the monothioacetalization of acetals
-
A novel polymer was synthesized by copolymerization of styrene monomer bearing dicyanoketene acetal functionality and ethylene glycol dimethacrylate, and used successfully as a recyclable π-acid catalyst in monothioacetalization of aromatic, aliphatic, acyclic, and cyclic acetals with thiophenol and phenylthiotrimethylsilane.
- Masaki, Yukio,Tanaka, Nobuyuki,Miura, Tsuyoshi
-
p. 5799 - 5802
(2007/10/03)
-
- Catalyst-dependent selective synthesis of O/S- and S/S-acetals from enol ethers
-
Enol ethers are reacted with mercaptanes to give the corresponding O/S- or S/S-acetals in medium to high yield. Either product can be formed selectively depending on the acid catalyst and the reaction time applied.
- Braga,Silveira,Dornelles,Zeni,Galarza,Wessjohann
-
p. 3155 - 3162
(2007/10/02)
-
- Monothioacetalization of acetals catalyzed by dicyanoketene acetals
-
A type of capto-dative olefin, dicyanoketene acetal such as dicyanoketene dimethyl acetal and ethylene acetal is introduced to be a novel type of π-acid catalyst for the monothioacetalization of acetals as well as the corresponding α,β-unsaturated systems. Particularly, the catalytic activity of dicyanoketene ethylene acetal was found to be superior to that of tetracyanoethylene and highly chemoselective in the crossover reaction of a ketone-, aldehyde-acetal, an alcohol THP-, and MOM-ether providing a ketone monothioacetal favorably.
- Miura, Tsuyoshi,Masaki, Yukio
-
p. 10477 - 10486
(2007/10/02)
-
- Dicyanoketene Acetals, a Novel Type of ?-Acid Catalyst for Monothioacetalization of Acetals
-
Dicyanoketene acetals such as dicyanoketene dimethyl acetal and ethylene acetal are introduced to be a novel type of ?-acid catalyst for the monothioacetalization of acetals.Particularly, the catalytic activity of dicyanoketene ethylene acetal was found to be superior to that of tetracyanoethylene and chemoselective in the crossover reaction of the monothioacetalization of a ketone-, an aldehyde-acetal and an alcohol THP-ether providing a ketone monothioacetal favorably.
- Miura, Tsuyoshi,Masaki, Yukio
-
p. 7961 - 7964
(2007/10/02)
-
- CONVERSION OF ACETALS INTO MONOTHIOACETALS, α-ALKOXYAZIDES AND α-ALKOXYALKYL THIOACETATES WITH MAGNESIUM BROMIDE
-
Magnesium bromide in ether has been found to be a very mild and highly efficient reagent for the conversion of acetals into the corresponding monothioacetals, α-alkoxyazides and α-alkoxyalkyl thioacetates.
- Kim, Sunggak,Park, Jung Ho,Lee, Sangphil
-
p. 6697 - 6700
(2007/10/02)
-
- ACTIVATION AND SYNTHETIC APPLICATIONS OF THIOSTANNANES. THIOALKOXYLATION OF ACETALS
-
The Sn-S bonds in thiostannanes, BunSn(SPh)4-n, are activated towards acetals in the presence of BF3*OEt2.Acetals of various aldehydes and ketones are converted into the corresponding monothioacetals under mild conditions.Employment of α-enal acetals induces Michael addition to give synthetically useful γ-alkoxyally sulfides.
- Sato, Tsuneo,Otera, Junzo,Nozaki, Hitosi
-
p. 1209 - 1218
(2007/10/02)
-
- Organotin-Mediated Preparation of Monothioacetals
-
Monothioacetals are obtained by treating the corresponding acetals with organotin thiophenoxides in the presence of BF3*OEt2.The reaction proceeds under mild conditions to provide the desired compounds with high selectivity.
- Sato, Tsuneo,Kobayashi, Takamitsu,Gojo, Tamehisa,Yoshida, Enji,Otera, Junzo,Nozaki, Hitosi
-
p. 1661 - 1664
(2007/10/02)
-