Enhancing Intermolecular Benzoyl‐Transfer Reactivity in Crystals by Growing a “Reactive” Metastable Polymorph by Using a Chiral Additive

摘要: Racemic 2,4-di-O-benzoyl-myo-inositol-1,3,5-orthoacetate, which normally crystallizes in a monoclinic form (form I, space group P2(1)/n) could be persuaded to crystallize out as metastable polymorph II, C2/c) by using small amount of either D- or L- 2,4-di-O-benzoyl-myo-inositol-1,3,5-orthoformate an additive the crystallization medium. The structurally similar enantiomeric was chosen scrutiny previous experimental results on racemic 2,4-di-O-benzoyl-myo-inositol-1,3,5-orthoacetate. Form II crystals can thermally transformed I at about 145 degrees C. relative organization molecules these dimorphs vary slightly terms helical assembly molecules, that is, electrophile (El)...nucleophile (Nu) and C-H...pi interactions, but minor variations have profound effect facility specificity benzoyl-group-transfer reactivity two crystal forms. While undergo clean intermolecular reaction, are less reactive non-specific benzoyl-group transfer leading mixture products. role played fine-tuning changes required molecular packing opens up possibility creating new polymorphs show varied physical chemical properties. Crystals D-2,6-di-O-benzoyl-myo-inositol-1,3,5-orthoformate (additive) did not facile (in contrast corresponding compound) due lack proper juxtaposition molecules.