77943-39-6 Usage
Chemical Properties
white to light yellow crystal powde
Uses
Different sources of media describe the Uses of 77943-39-6 differently. You can refer to the following data:
1. (4R,5S)-4-Methyl-5-phenyloxazolidinone is used as effective chiral auxiliary for conjugate addition asymmetric synthesis of (-)-aplysillamide B.
2. Evan′s chiral auxiliary (4R,5S)-(+)-4-Methyl-5-phenyl-2-oxazolidinone reacts with carboxylic acids to produce corresponding acyl derivatives in the presence of a diisopropylcarbodiimide reagent. It can also employed in the preparation of N-sulfinyloxazolidinone reagent (chiral sulfinyl transfer reagent), which reacts with nucleophiles such as Grignard reagents, enolates, and metalated amides to produce the chiral sulfoxides, sulfinate esters, and sulfonamides.
Preparation
Different sources of media describe the Preparation of 77943-39-6 differently. You can refer to the following data:
1. To a solution of (1S,2R)-norephedrine (40 g, 0.26 mol) in toluene (400 mL) was added diethyl carbonate (37 mL, 0.32 mol). The mixture was heated to reflux (under Ar) while 40 mL of solvent was removed through the use of a Dean–Stark apparatus. The mixture was allowed to cool for 20 min, and then sodium methoxide (1 g) was added. Upon reheating, an EtOH/toluene azeotropic mixture was removed at 75–77 °C. After 3 h, the reaction was complete and the temperature of the mixture had increased to 125 °C. The mixture was left to stand at room temperature for 16 h, whereupon (4R,5S)-4-methyl-5-phenyloxazolidin-2-one (40.6 g) crystallized and could be collected. The solvent was removed from the filtrate in vacuo and the residue was redissolved in EtOAc (250 mL). This solution was washed with brine (50 mL) and a precipitate was removed by filtration. The solvent was then removed in vacuo and toluene (50 mL) was added to the residue. Removal of the toluene by distillation yielded oily crystals of the oxazolidinone, which were washed with Et2O to afford 4.5 g (total 45 g, 97%).
2. A mechanically stirred mixture of (1S,2R)-norephedrine 710 (151 g, 1.00 mol) ([α]589 =+ 33.4 (c= 7, water)), as the hydrochloride salt, diphenyl carbonate (236 g, 1.10 mol), and anhydrous potassium carbonate (152 g, 1.10 mol) was heated at 110 °C for 4–6 h. The resultant mixture was then cooled to <60 °C. Excess diphenyl carbonate was hydrolyzed by adding methanol (600 mL) and heating the mixture under reflux for 0.5 h. Sufficient water (400–600 mL) was then added to dissolve the potassium carbonate. Methanol was removed in vacuo. The product and phenol were extracted into dichloromethane (3 × 1 L). The combined extracts were washed with 2 m aqueous sodium hydroxide (3 × 1 L) to remove the phenol, 1 m aqueous hydrochloric acid (1 × 1 L), and brine, dried over anhydrous magnesium sulfate, and concentrated in vacuo to give 195 g (110% mass balance) of a light-yellow solid. Recrystallization from toluene (600 mL) afforded 145–165 g (82–93%) of oxazolidinone 711 as a white crystalline solid.
Check Digit Verification of cas no
The CAS Registry Mumber 77943-39-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,7,9,4 and 3 respectively; the second part has 2 digits, 3 and 9 respectively.
Calculate Digit Verification of CAS Registry Number 77943-39:
(7*7)+(6*7)+(5*9)+(4*4)+(3*3)+(2*3)+(1*9)=176
176 % 10 = 6
So 77943-39-6 is a valid CAS Registry Number.
InChI:InChI=1/C10H11NO2/c1-7-9(13-10(12)11-7)8-5-3-2-4-6-8/h2-7,9H,1H3,(H,11,12)/t7-,9-/m1/s1
77943-39-6Relevant articles and documents
Asymmetric ammonium ylid rearrangements: the effect of nitrogen asymmetry
Sweeney,Tavassoli, Ali,Workman, James A.
, p. 11506 - 11512 (2006)
[2,3]-Sigmatropic rearrangements of allylic ammonium ylids derived from glycinoylcamphorsultams are highly selective in terms of relative and absolute stereocontrol only when acyclic alkenes are present. When chiral esters of ylids derived from N-methyltetrahydropyridine ('NMTP') undergo rearrangement, the reactions show exclusive cis-stereoselectivity but the products are obtained with virtually no absolute stereocontrol. These observations support the notion that sigmatropic rearrangements of N-chiral ammonium ylids are controlled by nitrogen stereogenicity.
Stereoselective synthesis of oxazolidin-2-ones via an asymmetric aldol/curtius reaction: Concise total synthesis of (?)-cytoxazone
Choi, Hosam,Choi, Joohee,Jang, Hanho,Lee, Kiyoun
, (2021/06/14)
Herein, we are reporting an efficient approach toward the synthesis of 4,5-disubstituted oxazolidin-2-one scaffolds. The developed approach is based on a combination of an asymmetric aldol and a modified Curtius protocol, which uses an effective intramolecular ring closure to rapidly access a range of oxazolidin-2-one building blocks. This strategy also permits a straightforward and concise asymmetric total synthesis of (?)-cytoxazone. Consisting of three steps, this is one of the shortest syntheses reported to date. Ultimately, this convenient platform would provide a promising method for the early phases of drug discovery.
Tandem copper and photoredox catalysis in photocatalytic alkene difunctionalization reactions
Reed, Nicholas L.,Herman, Madeline I.,Miltchev, Vladimir P.,Yoon, Tehshik P.
supporting information, p. 351 - 356 (2019/02/20)
Oxidative alkene difunctionalization reactions are important in synthetic organic chemistry because they can install polar functional groups onto simple non-polar alkene moieties. Many of the most common methods for these reactions rely upon the reactivity of pre-oxidized electrophilic heteroatom donors that can often be unstable, explosive, or difficult to handle. Herein, we describe a method for alkene oxyamination and diamination that utilizes simple carbamate and urea groups as nucleophilic heteroatom donors. This method uses a tandem copper–photoredox catalyst system that is operationally convenient. The identity of the terminal oxidant is critical in these studies. Ag(I) salts proved to be unique in their ability to turn over the copper cocatalyst without deleteriously impacting the reactivity of the organoradical intermediates.
