155189-76-7Relevant articles and documents
Lewis acid-catalyzed asymmetric hydroxymethylation of silicon enolates in aqueous media
Manabe, Kei,Ishikawa, Shunpei,Hamada, Tomoaki,Kobayashi, Shu
, p. 10439 - 10444 (2003)
Asymmetric hydroxymethylation of silicon enolates with formaldehyde in aqueous media has been achieved using praseodymium triflate and a chiral crown ether. Formaldehyde aqueous solution can be directly used for the reactions, and a water/THF mixture was found to be the best solvent system. This is the first example of catalytic asymmetric hydroxymethylation of silicon enolates.
Catalytic asymmetric hydroxymethylation of silicon enolates using an aqueous solution of formaldehyde with a chiral scandium complex
Ishikawa, Shunpei,Hamada, Tomoaki,Manabe, Kei,Kobayashi, Shu
, p. 12236 - 12237 (2004)
Catalytic asymmetric hydroxymethylation of silicon enolates has been achieved. In this reaction, an aqueous solution of formaldehyde can be used to realize an easy and safe procedure, and high enantioselectivities have been obtained. This is the first exa
Synthesis of a Bolm's 2,2′-Bipyridine Ligand Analogue and Its Applications
Bedná?ová, Eva,Dra?ínsky, Martin,Malatinec, ?tefan,Císa?ová, Ivana,Lamaty, Frédéric,Kotora, Martin
supporting information, p. 2869 - 2878 (2018/08/17)
A new method of synthesis of an analogue of Bolm's 2,2′-bipyridine ligand based on the catalytic [2+2+2] cyclotrimerization of 1-halodiynes with nitriles was developed. Crucial step of the whole synthesis turned out to be homodimerization of a substituted 2-bromopyridine to the corresponding bipyridine, that was studied and optimized. The newly prepared bipyridine (S,S)-2 was then tested as a chiral ligand in metal-catalyzed enantioselective reactions. Out of the studied reactions the most promising results were obtained in epoxide ring opening (82% yield, 98% ee) and Mukaiyama aldol reaction (>96% yield, 99/1 dr, 92% ee). In the case of Mukaiyama-aldol reaction as well as in the Michael addition, novel ligand 2 proved its robustness compared to Bolm's ligand as it was less sensitive to the purity of used reagents. (Figure presented.).
Enantioselective evans-tishchenko reduction of β-hydroxyketone catalyzed by lithium binaphtholate
Ichibakase, Tomonori,Nakatsu, Masato,Nakajima, Makoto
experimental part, p. 5008 - 5019 (2011/08/10)
Lithium diphenylbinaphtholate catalyzed the enantioselective Evans-Tishchenko reduction of achiral β-hydroxyketones to afford monoacyl-protected 1,3-diols with high stereoselectivities. In the reaction of racemic β-hydroxyketones, kinetic optical resolution occurred in a highly stereoselective manner.
