02437nas a2200277 4500008004100000022001400041245017600055210006900231260006700300300001000367490000700377520139300384653001801777653001401795653002201809653003201831653002101863653002101884653001701905653002601922100002301948700001701971700002401988700002702012856012002039 2014 eng d a0108-270100aCorrelation of the solid-state reactivities of racemic 2,4(6)-di-O-benzoyl-myo-inositol 1,3,5-orthoformate and its 4,4 `-bipyridine cocrystal with their crystal structures0 aCorrelation of the solidstate reactivities of racemic 246diObenz a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcNOV a1040+0 v703 a

Racemic 2,4(6)-di-O-benzoyl-myo-inositol 1,3,5-orthoformate, C21H18O8, (1), shows a very efficient intermolecular benzoyl-group migration reaction in its crystals. However, the presence of 4,4 `-bipyridine molecules in its cocrystal, C21H18O8 center dot C10H8N2, (1)center dot BP, inhibits the intermolecular benzoyl-group transfer reaction. In (1), molecules are assembled around the crystallographic twofold screw axis (b axis) to form a helical self-assembly through conventional O-H center dot center dot center dot O hydrogen-bonding interactions. This helical association places the reactive C6-O-benzoyl group (electrophile, El) and the C4-hydroxy group (nucleophile, Nu) in proximity, with a preorganized El center dot center dot center dot Nu geometry favourable for the acyl transfer reaction. In the cocrystal (1)center dot BP, the dibenzoate and bipyridine molecules are arranged alternately through OH center dot center dot center dot N interactions. The presence of the bipyridine molecules perturbs the regular helical assembly of the dibenzoate molecules and thus restricts the solid-state reactivity. Hence, unlike the parent dibenzoate crystals, the cocrystals do not exhibit benzoyl-transfer reactions. This approach is useful for increasing the stability of small molecules in the crystalline state and could find application in the design of functional solids.

10aacyl transfer10acocrystal10acrystal structure10adesign of functional solids10ahelical assembly10ahydrogen bonding10amyo-inositol10asolid-state reactions1 aTamboli, Majid, I.1 aBahadur, Vir1 aGonnade, Rajesh, G.1 aShashidhar, Mysore, S. uhttps://library.ncl.res.in/content/correlation-solid-state-reactivities-racemic-246-di-o-benzoyl-myo-inositol-135-002688nas a2200181 4500008004100000022001400041245018200055210006900237260007100306300001400377490000700391520188100398100002302279700002702302700002402329700002702353856012602380 2014 eng d a1528-748300aCrystal-to-crystal thermal phase transformation of polymorphs of isomeric 2,3-naphthalene diol ditoluates: mechanism and implications for molecular crystal formation and melting0 aCrystaltocrystal thermal phase transformation of polymorphs of i a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcOCT a4985-49960 v143 a

Isomeric para- (1) and meta- (2) ditoluate derivatives of naphthalene 2,3-diol exhibited polymorphism producing three (Forms 1I, 1II, 1III) and two (Forms 2I, 2II) polymorphs each, respectively, depending on the solvent and conditions of crystallization. Crystal forms 1I, 1II, and 2I could be obtained repeatedly, whereas crystal forms 1III and 2II were obtained (separately) in one of the crystallization experiments, each. All the crystal forms were stable at ambient conditions, except for Form 2II, which disintegrated to a powder over 45 days. In contrast, the ortho-ditoluate (3) of naphthalene 2,3-diol did not exhibit polymorphism; it yielded fibrous chiral crystals from different solvents/conditions. Crystal structure analysis of all these polymorphs revealed dominance of energetically similar weak intermolecular interactions such as CH center dot center dot center dot O, CH center dot center dot center dot pi, pi center dot center dot center dot pi, and their interplay in molecular aggregation resulting in polymorphic modifications. Differential scanning calorimetry (DSC), hot stage microscopy, single crystal and powder X-ray diffraction measurements revealed crystal-to-crystal thermal transformation of Forms 1I and 1II crystals to Form 1III crystals and Form 2II crystals to Form 2I crystals. The transformation of Form 1I and Form 1II crystals to Form 1III crystals can be viewed as progressive destabilization of the crystal lattice during heating and converting to metastable phase, whereas the conversion of Form 2II to Form 2I crystals can be considered as reorganization of an unstable crystalline phase to a stable crystalline phase. Hence comparative studies of the structure of stable, metastable, or transient crystals and crystal-to-crystal transformations involving these forms could aid in unraveling the process of crystallization.

1 aTamboli, Majid, I.1 aKrishnaswamy, Shobhana1 aGonnade, Rajesh, G.1 aShashidhar, Mysore, S. uhttps://library.ncl.res.in/content/crystal-crystal-thermal-phase-transformation-polymorphs-isomeric-23-naphthalene-diol-002400nas a2200181 4500008004100000022001400041245024500055210006900300260007100369300001400440490000700454520154000461100002302001700001702024700002402041700002702065856012602092 2015 eng d a1528-748300aCocrystallization of 2,3-dihydroxynaphthalene with its para-, meta-, and ortho-ditoluates: insight into cocrystal formation and clues for the construction of supramolecular assemblies capable of intermolecular acyl group transfer reactivity0 aCocrystallization of 23dihydroxynaphthalene with its para meta a a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcMAR a1226-12320 v153 a

2,3-Dihydroxynaphthalene forms 2:1 cocrystals with its p-ditoluate and 1:1 cocrystals with its m-ditoluate but not with the o-ditoluate. In 2:1 cocrystals of the p-ditoluate, naphthalene diol molecules form a dimeric motif through OH...O hydrogen bonding interactions. The adjacent dimers sandwich the molecules of p-ditoluate through C-H...pi interactions. In 1:1 cocrystals of the m-ditoluate, naphthalene diol molecules generate a zigzag pattern through O-H...O hydrogen bonding interaction involving -OH of the diol and the C=O of the m-ditoluate. Intermolecular toluoyl group transfer reaction was more facile in cocrystals of the p-ditoluate as compared to cocrystals of the m-ditoluate. This difference in reactivity is consistent with the relative geometry of the electrophile (El, C-O) and the nucleophile (Nu, OH) in these cocrystals. A comparison of the cocrystallization behavior and structure of the two cocrystals with their constituents suggests that the position of the methyl group is crucial for cocrystal formation. A survey of the CSD revealed that the incidence of polymorphism and cocrystals formation decreases (number of hits) in the order para- > ortho- > meta- for disubstituted benzene derivatives. This suggests that compounds prone to exhibit polymorphism have more propensities to form cocrystals as compared to those that resist polymorphism. This information could be useful while selecting cocrystal formers and construction of supramolecular functional assemblies with desired properties.

1 aTamboli, Majid, I.1 aBahadur, Vir1 aGonnade, Rajesh, G.1 aShashidhar, Mysore, S. uhttps://library.ncl.res.in/content/cocrystallization-23-dihydroxynaphthalene-its-para-meta-and-ortho-ditoluates-insight-001744nas a2200181 4500008004100000022001400041245021900055210006900274260000800343300001400351490000700365520096500372100002401337700002701361700002301388700002401411856012701435 2017 eng d a1528-748300aClues from crystal structures pave the way to access chiral myo-inositol derived versatile synthons: resolution of racemic 4-o-allyl-myo-inositol-1,3,5-orthoesters via corresponding dicamphanates by crystallization0 aClues from crystal structures pave the way to access chiral myoi cOCT a5432-54400 v173 aRacemic 4-O-allyl-myo-inositol-1,3,5-orthoesters were resolved as the corresponding diastereomeric dicamphanates by crystallization from alcoholic solvents. Crystals of the two diastereomers of myo-inositol orthoacetate and one diastereomer each of myo-inositol orthoformate and myo-inositol orthobenzoate were obtained in >99% purity, on gram scale. The configuration of all these diastereomers was established by conversion to known chiral myo-inositol derivatives as well as by single crystal structure analysis. It is interesting to note that the procedures for the separation of diastereomeric myo-inositol orthoesters could be evolved due to the knowledge of crystal growth and crystal structures of inositol derivatives of comparable molecular structures. Due to the synthetic versatility of myo-inositol orthoesters, the methods described provide rapid and convenient access to a variety of chiral inositol derivatives with high synthetic potential.1 aPatil, Nivedita, T.1 aShashidhar, Mysore, S.1 aTamboli, Majid, I.1 aGonnade, Rajesh, G. uhttps://library.ncl.res.in/content/clues-crystal-structures-pave-way-access-chiral-myo-inositol-derived-versatile-synthons00795nas a2200169 4500008004100000022001400041245026000055210006900315260000800384300000900392490000700401100002300408700001700431700002400448700002700472856012600499 2019 eng d a1528-748300aCocrystallization of 2,3-dihydroxynaphthalene with its para-, meta-, and ortho-ditoluates: insight into cocrystal formation and clues for the construction of supramolecular assemblies capable of intermolecular acyl group transfer reactivity (vol 15, pg 120 aCocrystallization of 23dihydroxynaphthalene with its para meta a cOCT a59980 v191 aTamboli, Majid, I.1 aBahadur, Vir1 aGonnade, Rajesh, G.1 aShashidhar, Mysore, S. uhttps://library.ncl.res.in/content/cocrystallization-23-dihydroxynaphthalene-its-para-meta-and-ortho-ditoluates-insight-1