3979-14-4Relevant academic research and scientific papers
Hydrogen-Bonding Assisted Catalytic Kinetic Resolution of Acyclic β-Hydroxy Amides
Porey, Arka,Mondal, Bhaskar Deb,Guin, Joyram
, p. 8786 - 8791 (2021/03/17)
Enantioenriched acyclic α-substituted β-hydroxy amides are valuable compounds in chemical, material and medicinal sciences, but their enantioselective synthesis remains challenging. A catalytic kinetic resolution (KR) of such amides with selectivity factor(s) up to >200 is developed via enantioselective acylation of primary alcohol with N-heterocyclic carbene. An enhanced selectivity for the catalytic KR process is realized using cyclic tertiary amine as base additive. Diastereomeric transition state models for the process are proposed to rationalize the origin of enantioselectivity.
Buscopan labeled with carbon-14 and deuterium
Latli, Bachir,Stiasni, Michael,Hrapchak, Matt,Li, Zhibin,Grinberg, Nelu,Lee, Heewon,Busacca, Carl A.,Senanayake, Chris H.
, p. 557 - 564 (2016/11/23)
Hyosine butyl bromide, the active ingredient in Buscopan, is an anticholinergic and antimuscarinic drug used to treat pain and discomfort caused by abdominal cramps. A straightforward synthesis of carbon-14– and deuterium-labeled Buscopan was developed using scopolamine, n-butyl-1-14C bromide, and n-butyl-2H9 bromide, respectively. In a second carbon-14 synthesis, the radioactive carbon was incorporated in the tropic acid moiety to follow its metabolism. Herein, we describe the detailed preparations of carbon-14– and deuterium-labeled Buscopan.
Copper-catalyzed intermolecular chloroazidation of α,β-unsaturated amides
Chen, Long,Xing, Haotian,Zhang, Huaibin,Jiang, Zhong-Xing,Yang, Zhigang
supporting information, p. 7463 - 7467 (2016/08/16)
A highly practical copper-catalyzed intermolecular chloroazidation of α,β-unsaturated amides has been described, giving a series of azidochlorides in good-to-excellent yields. The stable azidoiodine(iii) reagent and SOCl2 were used as azide and chlorine sources, respectively. The synthetic applications of this protocol were also explored by a variety of synthetically useful transformations.
Convenient procedure for the indium-mediated hydroxymethylation of active bromo compounds: Transformation of ketones into α-hydroxymethyl nitroalkanes
Soengas, Raquel G.,Estévez, Amalia M.
supporting information; experimental part, p. 2625 - 2627 (2010/12/18)
A very simple, safe and powerful method for the hydroxymethylation of 2-bromoesters and lactones under anhydrous conditions that avoids the use of gaseous formaldehyde is described. Moreover, under these conditions, bromonitroalkanes were converted into the corresponding α- monohydroxymethylated nitroalkanes, which are precursors of the corresponding α-amino acids. Considering the easy transformation of ketones into bromonitroalkanes, this represents a method for the formal synthesis of α-amino acids from ketones. Georg Thieme Verlag Stuttgart New York.
Dynamic kinetic resolution of racemic α-sulfonylaldehydes via asymmetric transfer hydrogenation
Wu, Guofeng,Zhu, Jinlong,Ding, Zhenhua,Shen, Zongxuan,Zhang, Yawen
supporting information; experimental part, p. 427 - 429 (2009/05/27)
Hydrogen transfer reduction of α-sulfonylaldehydes using HCOOH-Et3N system as hydrogen source and (S,S)-TsDPEN-based Ru(II) as catalyst proceeds with dynamic kinetic resolution, providing optically active β-sulfonyl primary alcohols in moderate-to-good yields and up to 90% ee.
Kinetic resolution of tropic acid ethyl ester and its derivatives by lipase PS
Atuu, Mary Rose,Mahmood, Syed J.,Laib, Frank,Hossain, M. Mahmun
, p. 3091 - 3101 (2007/10/03)
The first kinetic resolution of tropic acid ethyl ester (TAEE) with lipase PS and vinyl acetate as an acylating agent is reported. The resulting (S)-(-)-3-acetoxy tropic acid ethyl ester and (R)-(+)-tropic acid ethyl ester are produced in high yields and in excellent ee (87-94%). The method has been extended to resolve a variety of tropic acid ester derivatives. In addition, an improved method for the preparation of racemic mixtures of tropic acid ethyl ester and its derivatives from 3-hydroxy-2-phenylacrylic acid ethyl ester using NaBH4 in methanol is reported. This procedure is better than the previous ones because it is cleaner, safer and can be worked up easily. An improved method of deacylating the chiral 3-acetoxy tropic acid ethyl ester without any loss of stereochemical integrity using HCl/CH3OH is also reported.
