170108-73-3Relevant academic research and scientific papers
A facile method for the synthesis of enantiopure α-unsubstituted β- hydroxy esters
Wang, Ying-Chuan,Hwang, Jia-Yang,Chen, Yih-Cheng,Chuang, Shang-Chi,Yan, Tu-Hsin
, p. 1797 - 1800 (2000)
One-pot deacylation-debromination reactions involving the transesterification of the initial chiral α-bromo-β-hydroxy thioimide aldol adducts and subsequent Al-Hg mediated reductive cleavage of the C-Br bond allow for a facile synthesis of enantiopure β-h
Paracyclophane-based carbene-copper catalyst tuned by transannular electronic effects for asymmetric boration
Chen, Jianqiang,Duan, Wenzeng,Chen, Zhen,Ma, Manyuan,Song, Chun,Ma, Yudao
, p. 75144 - 75151 (2016/08/24)
A series of planar chiral carbene-copper complexes based on the [2.2]paracyclophane backbone with a pseudo-ortho substitution pattern have been synthesized and applied to asymmetric β-boration of α,β-unsaturated esters. As a result, transannular electronic effects of the substituent of the chiral catalyst have significant influence on the catalytic performance. A variety of chiral β-hydroxyl esters were obtained in excellent enantioselectivities (up to 97% ee) and yields (up to 99%).
(R)-(+)-N-Methylbenzoguanidine ((R)-NMBG) catalyzed acylative kinetic resolution of racemic 3-hydroxy-3-aryl-propanoates
Yamada, Akira,Nakata, Kenya
supporting information, p. 4697 - 4701 (2016/10/03)
(R)-(+)-N-methylbenzoguanidine ((R)-NMBG) functioned as an efficient acyl transfer catalyst for the acylative kinetic resolution of racemic β-hydroxy esters using cyclohexane carboxylic anhydride under mild reaction conditions. A tert-butyl ester moiety is necessary to achieve a high selectivity. The effects of the substituents on the aromatic rings of the substrates were systematically investigated, and diverse substrates participated in the reaction with good s-values (>20) irrespective of the type of substituents and their patterns, except for o-methoxy group.
Dimethylzinc-mediated, oxidatively promoted Reformatsky reaction of ethyl iodoacetate with aldehydes and ketones
Cozzi, Pier Giorgio,Mignogna, Alessandro,Vicennati, Paola
supporting information; experimental part, p. 975 - 978 (2009/05/27)
A practical and general Reformatsky reaction, promoted by oxidants and mediated by dimethylzinc, is described. The reaction is fast and runs at 0°C with aldehydes and ketones, under mild reaction conditions. Preliminary results obtained for the enantioselective version show that inexpensive chiral amino alcohols could be used in the challenging formation of enantioenriched quaternary stereogenic centers.
An in situ procedure for catalytic, enantioselective acetate aldol addition. Application to the synthesis of (R)-(-)-epinephrine
Singer, Robert A.,Carreira, Erick M.
, p. 927 - 930 (2007/10/03)
We report an in situ preparation of catalyst 3 which substantially simplifies the experimental procedure for the enantioselective, catalytic acetate aldol addition reaction. The addition of Me3SiCl and Et3N circumvents the azeotropic removal of the released isopropanol upon treating ligands 1 and 2 with Ti(O(i)Pr)4. Importantly, this new procedure maintains the salient features of the catalytic process we originally described: high yields and enantioselectivities, low catalyst loads, and convenient reaction times and temperatures. We have applied the new procedure to an efficient synthesis of (R)-(-)-epinephrine from commercially available reagents in an overall yield of 45%.
ASYMMETRIC ALDOL-TYPE REACTION BETWEEN BOTH A CHIRAL KETENE SILYL ACETALS OF ACETIC ACID ESTERS AND ALDEHYDES BY USE OF A CHIRAL PROMOTER
Mukaiyama, Teruaki,Kobayashi, Shu,Sano, Tetsuya
, p. 4653 - 4662 (2007/10/02)
Highly enantioselective aldol-type reaction between achiral ketene silyl acetals of acetic acid esters and achiral aldehydes is successfully carried out by the use of a chiral diamine coordinated tin (II) trifluoromethanesulfonate (tin (II) triflate) and tributyltin fluoride.The structure of this new promoter and the mechanism of the present asymmetric aldol-type reaction are discussed.
Asymmetric Aldol-type Reaction between Both Achiral Ketene Silyl Acetals and Aldehydes by the Use of a Chiral Promoter
Kobayashi, Shu,Sano, Tetsuya,Mukaiyama, Teruaki
, p. 1319 - 1322 (2007/10/02)
Highly enantioselective aldol-type reaction of achiral ketene silyl acetals with achiral aldehydes is carried out by the use of a chiral promoter, a combined use of chiral diamine coordinated tin(II) triflate and tributyltin fluoride.
