1,1′-Bi-2-naphthol

413087241 1,1-Bi-2-naphthol R-BINOL-2D-skeletal.png Skeletal formula of R-BINOL S-BINOL-2D-skeletal.png Skeletal formula of S-BINOL R-BINOL-3D-balls.png Ball-and-stick model of R-BINOL S-BINOL-3D-balls.png Ball-and-stick model of S-BINOL (R)-(+)-BINOL (S)-(−)-BINOL [1,1-Binaphthalene]-2,2-diol 1,1-Bi-2-naphthol 1,1-Binaphthol BINOL Binol correct chemspider 11269 11762 1/C20H14O2/c21-17-11-9-13-5-1-3-7-15(13)19(17)20-16-8-4-2-6-14(16)10-12-18(20)22/h1-12,21-22H PPTXVXKCQZKFBN-UHFFFAOYAX C1=CC=C2C(=C1)C=CC(=C2C3=C(C=CC4=CC=CC=C43)O)O (R/S) correct EBI 138718 correct chemspider 1S/C20H14O2/c21-17-11-9-13-5-1-3-7-15(13)19(17)20-16-8-4-2-6-14(16)10-12-18(20)22/h1-12,21-22H correct chemspider PPTXVXKCQZKFBN-UHFFFAOYSA-N 602-09-5 (R/S) 18531-94-7 (R)-(+) 18531-99-2 (S)-(−) correct FDA 25AB254328 (R/S) correct FDA M6IDZ128WT (R)-(+) correct FDA 54OT5RRV4C (S)-(−) 20 14 2 286.32 g/mol 205 to 211 Datasheet, chemexper.com 1,1-Bi-2-naphthol (BINOL) is an organic compound that is often used as a ligand for transition-metal catalysed asymmetric synthesis. BINOL has axial chirality and the two enantiomers can be readily separated and are stable toward racemisation. The specific rotation of the two enantiomers is 35.5° (c = 1 in THF), with the R enantiomer being the dextrorotary one. BINOL is a precursor for another chiral ligand called BINAP. The volumetric mass density of the two enantiomers is 0.62 g cm−3.January 2022 Preparation The organic synthesis of BINOL is not a challenge as such but the preparation of the individual enantiomers is. (S)-BINOL can be prepared directly from an asymmetric oxidative coupling of 2-naphthol with copper(II) chloride. The chiral ligand in this reaction is (S)-(+)-amphetamine. Brussee J. Jansen A. C. A. 1983 A highly stereoselective synthesis of S-(−)-[1,1-binaphthalene]-2,2-diol Tetrahedron Letters 24 31 3261–3262 10.1016/S0040-4039(00)88151-4 400px Racemic BINOL can also be produced using iron(III) chloride as an oxidant. The mechanism involves complexation of iron(III) into the hydroxyl, followed by a radical coupling reaction of the naphthol rings initiated by iron(III) reducing into iron(II). Optically active BINOL can also be obtained from racemic BINOL by optical resolution. In one method, the alkaloid N-benzylcinchonidinium chloride forms a crystalline inclusion compound. The inclusion compound of the (S)-enantiomer is soluble in acetonitrile but that of the (R)-enantiomer is not."RESOLUTION OF 1,1'-BI-2-NAPHTHOL" https://web.archive.org/web/20120716191712/http://www.orgsyn.org/orgsyn/prep.asp?prep=v76p0001 2012-07-16 , Dongwei Cai, David L. Hughes, Thomas R. Verhoeven, and Paul J. Reider, in Organic Syntheses Coll. Vol. 10, p.93; Vol. 76, p.1 In another method BINOL is esterified with pentanoyl chloride. The enzyme cholesterol esterase hydrolyses the (S)-diester but not the (R)-diester. The (R)-dipentanoate is hydrolysed in a second step with sodium methoxide."(S)-(−)- and (R)-(+)-1,1-bi-2-naphthol" https://web.archive.org/web/20050418112746/http://www.orgsyn.org/orgsyn/prep.asp?prep=CV9P0077 2005-04-18 , Romas J. Kazlauskas in Organic Syntheses, Coll. Vol. 9, p.77; Vol. 70, p.60 The third method employs HPLC with chiral stationary phases. Landek G. Vinković M. Kontrec D. Vinković V. 2006 Influence of mobile phase and temperature on separation of 1,1-binaphthyl-2,2-diol enantiomers with brush type chiral stationary phases derived from L-leucine Chromatographia 64 7–8 469–473 10.1365/s10337-006-0041-5 95785346 BINOL derivatives thumb|left|162px|Structure of a chiral phosphoric acid derived from BINOL.10.1021/cr5001496 Complete Field Guide to Asymmetric BINOL-Phosphate Derived Brønsted Acid and Metal Catalysis: History and Classification by Mode of Activation; Brønsted Acidity, Hydrogen Bonding, Ion Pairing, and Metal Phosphates 2014 Parmar Dixit Sugiono Erli Raja Sadiya Rueping Magnus Chemical Reviews 114 18 9047–9153 25203602 free Aside from the starting materials derived directly from the chiral pool, (R)- and (S)-BINOL in high enantiopurity (>99% enantiomeric excess) are two of the most inexpensive sources of chirality for organic synthesis, costing less than US$0.60 per gram when purchased in bulk from chemical suppliers.Yang Jin-Fei Wang Rong-Hua Wang Yin-Xia Yao Wei-Wei Liu Qi-Sheng Ye Mengchun 2016-10-11 Ligand-Accelerated Direct C−H Arylation of BINOL: A Rapid One-Step Synthesis of Racemic 3,3-Diaryl BINOLs Angewandte Chemie International Edition en 55 45 14116–14120 10.1002/anie.201607893 27726256 1433-7851 As a consequence, it serves as an important starting material for other sources of chirality for stereoselective synthesis, both stoichiometric and substoichiometric (catalytic). Many important chiral ligands are constructed from the binaphthyl scaffold and ultimately derived from BINOL as a starting material, BINAP being one of the most well known and important. The compound aluminium lithium bis(binaphthoxide) (ALB) is prepared by reaction of BINOL with lithium aluminium hydride.A practical large-scale synthesis of enantiomerically pure 3-[bis(methoxycarbonyl)methyl]cyclohexanone via catalytic asymmetric Michael reaction Tetrahedron, Volume 58, Issue 13, 25 March 2002, Pages 2585–2588 Youjun Xu, Ken Ohori, Takashi Ohshima, Masakatsu Shibasaki 10.1016/S0040-4020(02)00141-2 In a different stoichiometric ratio (1:1 BINOL/LiAlH4 instead of 2:1), the chiral reducing agent BINAL (lithium dihydrido(binaphthoxy)aluminate) is produced.Gopalan Aravamudan S. Lithium Aluminum Hydride-2,2-Dihydroxy-1,1-binaphthyl 2001-04-15 Encyclopedia of Reagents for Organic Synthesis John Wiley & Sons, Ltd en 10.1002/047084289x.rl041 0471936235 Jacobs Hollie K. 450px It has been employed in an asymmetric Michael reaction with cyclohexenone and dimethyl malonate: 343px See also Shibasaki catalysts References Category:2-Naphthols Category:Dimers (chemistry) Category:Symmetrical biaryls Category:Atropisomers