NOVEL PROCESS FOR THE PREPARATION OF R-PHENYLACETYLCARBINOL AND β-AMINOALCOHOLS
Disclosed herein is a process for the manufacture of (R)-phenylacetylcarbinol ((R)-PAC), (1R,2S). Ephedrine and its salts, (1R,2S)-norephedrine and its salts and 1-(Phenyl/Substituted phenyl)-2-(amino/alkylamino/dialklyamino) propan-1-ol and its salts, by enzymatic reduction of α-isonitrosopropiophenone (INP) and substituted α-isonitrosopropiophenone (substituted INP). The β-amino alcohols, produced by the process of present invention gives their corresponding diastereomers on Walden inversion. The present preparation process of (R)-PAC with (R)-PAC oxime as an intermediate has the advantage, that propiophenone as a key raw material which is easily available and has a low-price, operationally simple with high yield and a single process leading to the synthesis of several 1,2-aminoalcohol/ β- aminoalcohols active pharmaceutical ingredients. The design approach of the process is to reduce environmental impact of the product by comparing to the present manufacturing process.
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(2020/07/14)
A short enantioselective synthesis of ephedrine, amphetamine and their analogues via two stereocentered Co(III)-catalyzed hydrolytic kinetic resolution of racemic syn-benzyloxy epoxide
An efficient route for the synthesis of 6 drugs belonging to phenethylamine and amphetamine classes in excellent overall yields and high optical purity has been described. The strategy involves introduction of stereogenic centers by means of two-stereocentered Co(III)-catalyzed hydrolytic kinetic resolution (HKR) of racemic syn-benzyloxy epoxide followed by Pd-catalyzed regioselective cationic hydrogenation of amino alcohols as the key reactions.
Lalwani, Komal G.,Sudalai, Arumugam
supporting information
p. 6488 - 6490
(2015/11/16)
An efficient synthesis of aziridines from ephedrines
The reaction of chlorodeoxyephedrine hydrochlorides with one, two, and three molar equivalents of base was studied. Isochlorodeoxypseudoepherines were identified and assigned by 1H and 13C NMR data as intermediate compounds in the formation of cis-aziridines. Erythro and threo ephedrinethylethers were isolated as new compounds and analyzed by spectroscopic data. In addition, the erythro isomer was studied by X-ray diffraction.
Cruz, Alejandro,Padilla-Martinez, Itzia Irene,Garcia-Baez, Efren V.
scheme or table
p. 909 - 913
(2010/08/19)
Gamma-polymorph of a substituted pyrazoline, its preparation and use as medicaments
The present invention relates to the γ-Polymorph of (R)-N-piperidinyl-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4,5-dihydro-1H-pyrazole-3-carboxamide, methods for its preparation, medicaments comprising this compound as well as their use for the preparation of a medicament for the treatment of humans and animals.
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(2008/12/06)
Method of resolving racemic mixtures
PCT No. PCT/EP96/04030 Sec. 371 Date Feb. 26, 1998 Sec. 102(e) Date Feb. 26, 1998 PCT Filed Sep. 13, 1996 PCT Pub. No. WO97/11927 PCT Pub. Date Apr. 3, 1997A process for resolving racemates of compounds of the formula I in which a, A, B, D, E, F, M, Q and R have the meanings given in the description is described. The process is carried in a manner known per se but using the optical antipodes of derivatives of phenoxypropionic acid. Also described are salts of deprenyl, ephedrine or tetrahydropapaverine with a phenoxypropionic acid of the formula in which U and T have the meaning stated in the description, and which result as intermediate in the racemate resolution.
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(2008/06/13)
2-(Penta-1,3-dienyl)oxazolidines: Synthesis of hydroxylated piperidines by a stereoselective Diels-Alder reaction
Hexa-2,4-dienal condensed with (-)-ephedrine to give predominantly the oxazolidine 4, which underwent a stereoselective Diels-Alder reaction with benzyl nitrosoformate to give the cycloadducts 9 and 10 in a ca 5:2 ratio. Further transformations of 9 to give the optically active mono- and tri-hydroxypiperidine derivatives 11 and 15 have also been performed.
Hussain,Wyatt
p. 2123 - 2130
(2007/10/02)
Resolution of dl-allethrolone
A novel process for the resolution of dl-allethrolone or 2-allyl-4-hydroxy-3-methyl-2-cyclopentene-1-one whose chrysanthemic acid esters have insecticidal activity and to novel intermediates.