Amplification of Optical Activity by Crystallization in the Presence of Tailor-Made Additives. The “Inversion Rule”

Addadi, Lia; Mil, J. Van; Gati, E.; Lahav, Meir

doi:10.1007/978-94-009-8420-2_47

Cited by 19 publications

(22 citation statements)

References 16 publications

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“…The chiral crystallization of an achiral compound is of great interest in terms of the generation of optical activity simply by crystallization, − and chiral crystals have been used as chiral precursors in asymmetric synthesis − and are associated with the origin of life. − We have previously reported that some aromatic amides, − aromatic sulfonamides, , and a benzene-1,3,5-tricarboxylic acid derivative show chiral crystallization phenomena. This type of crystallization, however, does not occur very frequently: only 5–10% of achiral compounds can be crystallized as chiral crystals, − and the mechanism of the crystallization is still unknown.…”

Section: Introductionmentioning

confidence: 99%

Characteristic Hydrogen Bonding Observed in the Crystals of Aromatic Sulfonamides: 1D Chain Assembly of Molecules and Chiral Discrimination on Crystallization

Kikkawa

Masu

Katagiri

et al. 2019

Crystal Growth & Design

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N-Phenylbenzenesulfonamides exist preferentially in (+)-or (−)-synclinal conformations, which place the aromatic rings at both ends in the same direction with a twist. We have systematically analyzed the crystal structure of secondary aromatic sulfonamides bearing methyl, ethyl, and/ or methoxy groups on the benzene rings. Intermolecular hydrogen bonding between the sulfonamide protons and sulfonyl oxygens was observed in 81 out of 85 crystals. The intermolecular hydrogen-bonding patterns could be classified into four types, i.e. Dimeric, Zigzag, Helical, and Straight patterns, with retention of the synclinal conformation of the sulfonamide moiety. We investigated the relationship between the hydrogen-bonding pattern and the proportion of the compounds that show chiral crystallization. On the basis of our classification of the intermolecular hydrogen bonds of aromatic sulfonamides, the crystals with Dimeric and Zigzag patterns, which both have enantiomeric synclinal conformers, intrinsically become achiral, except for kryptoracemates. In contrast, a high proportion of compounds with Helical or Straight patterns in the crystals showed chiral crystallization. Our classification is useful for discussion regarding the chirality of molecular assemblies, on the basis of the conformational chirality of the molecules in the crystal.

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Section: Introductionmentioning

confidence: 99%

Characteristic Hydrogen Bonding Observed in the Crystals of Aromatic Sulfonamides: 1D Chain Assembly of Molecules and Chiral Discrimination on Crystallization

Kikkawa

Masu

Katagiri

et al. 2019

Crystal Growth & Design

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“…Up to now, absolute asymmetric synthesis has been limited to the application of physical chiral forces such as circularly polarized light and chiral magnetic fields . Of course, Soai’s reaction and asymmetric synthesis using the chirality of crystals generated by the crystallization of prochiral materials is also considered to be an absolute asymmetric synthesis. , These processes are of great interest to many scientists in a variety of areas because absolute asymmetric synthesis could support the hypothesis of the origin of homochirality on the primitive Earth …”

Section: Introductionmentioning

confidence: 99%

Asymmetric Diels–Alder Reaction Involving Dynamic Enantioselective Crystallization

Uemura¹,

Toyoda²,

Ishikawa³

et al. 2018

J. Org. Chem.

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Asymmetric Diels-Alder reaction was achieved under achiral conditions. Reaction of prochiral 2-methylfuran and N-phenylmaleimide in heptane or hexane solution at 80 °C efficiently gave a conglomerate crystal of exo-type Diels-Alder adduct selectively, and continuous suspension of the reaction mixture with glass beads promoted attrition-enhanced deracemization, leading to an optically active exo-adduct in 90% ee.

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“…Absolute asymmetric synthesis is a phenomenon that is of great interest in many research fields because it is closely related to homochirality and the origin of life on Earth. − It is significant to realize the absolute asymmetric reaction of flavanones that are widespread in natural plants and important in the pharmaceutical field.…”

Section: Discussionmentioning

confidence: 99%

Attrition-Enhanced Deracemization and Absolute Asymmetric Synthesis of Flavanones from Prochiral Precursors

Shimizu

Uemura

Yoshida

et al. 2020

Crystal Growth & Design

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Seven racemic 5,7-dimethoxyflavanones afforded conglomerate crystals upon recrystallization from a solvent. Three methodologies were investigated to achieve asymmetric transformation based on dynamic crystallization of the chiral conglomerate system. The first was chiral symmetry breaking of racemic flavanones by attrition-enhanced deracemization. Continuous suspension of racemic flavanones in a small amount of propanol in the presence of a base (1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)) and glass beads promoted chiral symmetry breaking and converted the flavanones to crystals of (+)-or (−)-enantiomers with 78 to 99% ee. The second method involved cyclization of the intermediate aldol product to give optically active flavanone with 90% ee involving a reversible oxa-Michael addition reaction with attrition-enhanced deracemization. The third was a reaction starting from prochiral 2-hydroxy-4,6dimethoxyacetophenone and 2-naphthaldehyde under basic conditions, which gave the corresponding flavanone in 89% ee.F lavanones (I) are among the most prevalent and valuable natural products, and their derivatives are widespread in many plants, fruits, vegetables, and pharmaceutical materials (Figure 1, II−IX). 1−7 Many flavanones with hydroxy or methoxy groups at the 5 and 7 positions show bioactivities, including antibacterial, antimalarial, anti-inflammatory, antipyretic, antiarrhythmic, antiasthmatic, antiulcerative, antineoplastic, and HIV-1 IN inhibitory effects. 8−14

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Amplification of Optical Activity by Crystallization in the Presence of Tailor-Made Additives. The “Inversion Rule”

Cited by 19 publications

References 16 publications

Characteristic Hydrogen Bonding Observed in the Crystals of Aromatic Sulfonamides: 1D Chain Assembly of Molecules and Chiral Discrimination on Crystallization

Characteristic Hydrogen Bonding Observed in the Crystals of Aromatic Sulfonamides: 1D Chain Assembly of Molecules and Chiral Discrimination on Crystallization

Asymmetric Diels–Alder Reaction Involving Dynamic Enantioselective Crystallization

Attrition-Enhanced Deracemization and Absolute Asymmetric Synthesis of Flavanones from Prochiral Precursors

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