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Chiral Auxiliaries and Optical Resolving Agents

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Chiral Auxiliaries and Optical Resolving Agents Chiral Auxiliaries and Optical Resolving Agents Most bioactive substances are optically active. For instance, if This brochure introduces a variety of chiral auxiliaries and a substance is synthesized as a racemic compound, its optical resolving agents. We hope that it will be useful for your enantiomer may show no activity or even undesired bioactivity. research of the synthesis of optically active compounds. Thus, methods to gain enantiopure compounds have been Additionally, TCI has some brochures introducing chiral developed. When synthesizing enantiopure compounds, the compounds for the chiral pool method in “Chiral Building Blocks”, methods are roughly divided into three methods. “Terpenes”, “Amino Acids” and other brochures. Sugar derivatives are also introduced in a catalog, “Reagents for Glyco Chemistry Chiral pool method: & Biology”, and category pages of sugar chains. Furthermore, The method using an easily available chiral compound as a TCI has many kinds of catalysts for asymmetric synthesis and starting material like an amino acid or sugar. introduce them in brochures such as “Asymmetric Synthesis” and Asymmetric synthesis: “Asymmetric Organocatalysts”, and other contents. The method to introduce an asymmetric point to compounds You can search our information through “asymmetric synthesis” without an asymmetric point. Syntheses using achiral as a keyword. auxiliaries are included here. Optical resolution: The method to separate a racemic compound into two ● Reactions with Chiral Auxiliaries enantiomers. The direct method using a chiral column and One of the most famous named reactions using chiral auxiliaries1) the indirect method to separate two enantiomers using is the Evans aldol reaction.2) This reaction is quite useful because optical resolving agents to convert into diastereomers are this reaction can efficiently introduce two asymmetric carbons into examples. chain-shaped compounds and the stereochemistry of the product can be expected. Additionally, N-acyloxazolidinones are Chiral pool synthesis commercially available and can be prepared from amino acid OH derivatives and the chiral auxiliaries are removed by the hydrolysis O HO or the conversion to Weinreb amide, so that it is superior in ease HO Chiral compounds OH of use. Furthermore, all of the diastereomers can be synthesized OH by maintaining the chiral auxiliaries and Lewis acids.3) Asymmetric synthesis BBu2 chiral catalyst O O O O O 1 Bu BOTf O H OH R 2 1 2 R 2 N iPr2NEt[D1599] R H * O O N R1 R2 R1 R2 CH3 CH3 CH3 Asymmetric synthesis with chiral auxiliaries CH3 OH O Z-enolate O R CHO O CH3 R X* iPr O O OH X* O CH3 N Bu X*: chiral auxiliary 2 B O N R O Bu R1 2 O Optical resolution R iPr R1 NH2 NH2 HO2CR* HO2CR* chiral R1 R2 R1 R2 NH2 carboxylic acid Crystallized R1 R2 NH2 HO2CR* R1 R2 Not crystallized 2 Please inquire for pricing and availability of listed products to our local sales representatives. Please inquire for pricing and availability of listed products to our local sales representatives. Chiral Auxiliaries and Optical Resolving Agents The Evans aldol reaction is applicable to larger scales. For example, the research group of Novartis used this reaction in the References large-scale synthesis of discodelmoride4) and they implemented 1) reviews of chiral auxiliaries: the below reaction at the 30 kg scale, which afforded the a) W. Oppolzer, Tetrahedron 1987, 43, 1969. intermediate 1 in high diastereoselectivity and enantioselectivity. b) H. Waldmann, Synthesis 1994, 535. c) V. Farina, J. T. Reeves, C. H. Senanayake, J. J. Song, Chem. Rev. 2006, 106, Ph 4) 2734. d) X. Salom-Roig, C. Bauder, Synthesis 2020, 52, 535. N O CH Ph 3 2) a) D. A. Evans, J. Bartroli, T. L. Shih, J. Am. Chem. Soc. 1981, 103, 2127. O O CH3 [B2165] CH3 CH3 b) review: D. A. Evans, J. M. Takacs, L. R. McGee, M. D. Ennis, D. J. Mathre, PMBO O CHO Bu2BOTf PMBO N J. Bartroli, Pure Appl. Chem. 1981, 53, 1109. iPr2NEt[D1599] 3) a) M. A. Walker, C. H. Heathcock, J. Org. Chem. 1991, 56, 5747. CH2Cl2 OH O O 1 b) M. T. Crimmins, B. W. King, E. A. Tabet, J. Am. Chem. Soc. 1997, 119, 7883. c) D. A. Evans, J. S. Tedrow, J. T. Shaw, C. W. Downey, J. Am. Chem. Soc. 2002, 124, 392. d) D. A. Evans, C. W. Downey, J. T. Shaw, J. S. Tedrow, J. Am. Chem. Soc. 2002, ● Optical Resolution 124, 392. Optical resolution5) is used in the manufacture of medicines even 4) S. J. Mickel, G. H. Sedelmeier, D. Niederer, R. Daeffler, A. Osmani, K. Schreiner, now, although it has some disadvantages as follows: theoretically, M. Seeger-Weibel, B. Bérod, K. Schaer, R. Gamboni, S. Chen, W. Chen, C. T. half of the substance will be lost; a selection process of the Jagoe, F. R. Kinder, M. Loo, K. Prasad, O. Repič, W.-C. Shieh, R.-M. Wang, reagents for optical resolution and separation of the reagents is L. Waykole, D. D. Xu, S. Xue, Org. Proc. Res. Dev. 2004, 8, 92. needed. However, if the undesired enantiomer can be racemized, 5) reviews of optical resolution: it will be possible to do optical resolution again and the recovery a) A. Collet, M. J. Brienne, J. Jacques, Chem. Rev. 1980, 80, 215. rate of the desired product will be raised. b) E. Fogassy, M. Nógrádi, D. Kozma, G. Egri, E. Pálovicsc, V. Kiss, Org. Biomol. Chem. 2006, 4, 3011. c) F. Faigl, E. Fogassy, M. Nógrádi, E. Pálovics, J. Schindler, Tetrahedron R X* R Asymmetry 2008, 19, 519. X* Crystallized d) S. H. Wilen, A. Collet, J. Jacques, Tetrahedron 1977, 33, 2725. R S + S X* Not crystallized racemization Please inquire for pricing and availability of listed products to our local sales representatives. Please inquire for pricing and availability of listed products to our local sales representatives. 3 Chiral Auxiliaries and Optical Resolving Agents B2907 1g 5g B2908 1g 5g O O Chiral Auxiliaries Sulfinamides (CH3)3CSNH2 (CH3)3CSNH2 (R)-(+)-tert-Butylsulfinamide (S)-(-)-tert-Butylsulfinamide CAS RN: 196929-78-9 CAS RN: 343338-28-3 T2069 1g 5g T2814 200mg 1g B1755 1g 5g 25g B1759 1g 5g O O CH3 O O CH3 CH3O C C O C CH3 H C C O C CH3 O O N N CH3 CH3 CH3 S NH2 CH3 S NH2 Oxazolidines CH3 CH3 O O CH3 CH3 (S)-(-)-3-Boc-4-methoxycarbonyl- (S)-(-)-3-Boc-4-formyl- (S)-(+)-p-Toluenesulfinamide (R)-(-)-p-Toluenesulfinamide 2,2-dimethyl-1,3-oxazolidine 2,2-dimethyl-1,3-oxazolidine CAS RN: 188447-91-8 CAS RN: 247089-85-6 CAS RN: 108149-60-6 CAS RN: 102308-32-7 B1754 5g 25g B1786 5g 25g A2095 1g 5g B2165 1g 5g 25g B2166 1g 5g O CH3 O CH3 H2N NH NH NH N N O O O O O O O O O O (S)-4-(4-Aminobenzyl)- (R)-(-)-4-Benzyl-3-propionyl- (S)-(+)-4-Benzyl-3-propionyl- (S)-4-Benzyl-2-oxazolidinone (R)-4-Benzyl-2-oxazolidinone 2-oxazolidinone 2-oxazolidinone 2-oxazolidinone CAS RN: 90719-32-7 CAS RN: 102029-44-7 CAS RN: 152305-23-2 CAS RN: 131685-53-5 CAS RN: 101711-78-8 I0451 1g 5g 25g I0572 1g 5g 25g I0573 1g 5g I0594 1g 5g I0575 1g CH3 CH3 CH3 O CH3 O CH3 CH2CH3 CH2CH3 CH3 CH3 CH3 CH3 CH3 NH NH N N NH O O O O O O O O S S (S)-(+)-4-Isopropyl-3-propionyl- (R)-(-)-4-Isopropyl- (S)-4-Isopropylthiazolidine- (S)-4-Isopropyl-2-oxazolidinone (R)-4-Isopropyl-2-oxazolidinone 2-oxazolidinone 3-propionyl-2-oxazolidinone 2-thione CAS RN: 17016-83-0 CAS RN: 95530-58-8 CAS RN: 77877-19-1 CAS RN: 89028-40-0 CAS RN: 76186-04-4 I0761 1g 5g I0762 1g 5g P1307 5g 25g P1308 5g 25g P1959 1g CH3 CH3 CH3 CH3 NH NH O O O O NH NH NH O O O O S S (4R)-(+)-4-Isopropyl- (4S)-(-)-4-Isopropyl- (R)-4-Phenylthiazolidine- 5,5-diphenyl-2-oxazolidinone 5,5-diphenyl-2-oxazolidinone (R)-(-)-4-Phenyl-2-oxazolidinone (S)-(+)-4-Phenyl-2-oxazolidinone 2-thione CAS RN: 191090-32-1 CAS RN: 184346-45-0 CAS RN: 90319-52-1 CAS RN: 99395-88-7 CAS RN: 110199-18-3 P1960 1g B2103 1g 5g B2104 1g 5g A1534 1g CH3 CH3 CH3 CH SO CH SO 3 2 CH 3 2 CH2 CH3 SO2 CH N 2 N N 2 CH3 OH CH3 OH CH3 O CH3 CH3 CH3 CH3 NH Aminoalcohol O S S Derivatives (1R,2S)-N-Benzyl- (1S,2R)-N-Benzyl- (1R,2S)-N-Benzyl- (S)-4-Phenylthiazolidine- N-(mesitylenesulfonyl)- N-(mesitylenesulfonyl)- N-(mesitylenesulfonyl)- 2-thione norephedrine norephedrine O-acetylnorephedrine CAS RN: 185137-29-5 CAS RN: 187324-63-6 CAS RN: 187324-64-7 CAS RN: 240423-74-9 A1535 1g P1371 1g C1324 1g 5g C1325 1g 5g CH CH3 3 CH SO CH3 CH3 CH3 CH3 CH3 SO2 CH 3 2 CH2 N 2 N CH3 O CH3 CH3 O CH3 CH3 CH3 O O Camphor- HN NH S S (1S,2R)-N-Benzyl- (1R,2S)-N-Benzyl- sultams O O N-(mesitylenesulfonyl)- N-(mesitylenesulfonyl)-O- O O O-acetylnorephedrine propionylnorephedrine (+)-10,2-Camphorsultam (-)-10,2-Camphorsultam CAS RN: 240423-53-4 CAS RN: 187324-66-9 CAS RN: 108448-77-7 CAS RN: 94594-90-8 B5518 1g 5g T1490 100mg 1g T1491 100mg 1g T2578 1g 5g O H OH OH N CH3 N O Others CH CH (R)-N-(2-Benzoylphenyl)- 3 S 3 1-benzylpyrrolidine- (1R,2S)-(-)-trans-2-Phenyl- (1S,2R)-(+)-trans-2-Phenyl- (1R,4R,5R)-4,7,7-Trimethyl- 2-carboxamide 1-cyclohexanol 1-cyclohexanol 6-thiabicyclo[3.2.1]octane CAS RN: 105024-93-9 CAS RN: 98919-68-7 CAS RN: 34281-92-0 CAS RN: 5718-75-2 4 Please inquire for pricing and availability of listed products to our local sales representatives.
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