00686nas a2200181 4500008004100000022001400041245006200055210006200117260000800179300000900187490000700196653012600203100002400329700001800353700001900371700002000390856009400410 2014 eng d a2053-273300aSupramolecular synthon hierarchy in bumetanide cocrystals0 aSupramolecular synthon hierarchy in bumetanide cocrystals cFEB aC7210 v7010aNovel cocrystals of sulfonamide drug Bumetanide with carboxamides are developed based on supramolecular synthons approach1 aAllu, Suryanarayana1 aBolla, Geetha1 aTothadi, Srinu1 aNangia, Ashwini uhttps://library.ncl.res.in/content/supramolecular-synthon-hierarchy-bumetanide-cocrystals01861nas a2200169 4500008004100000245007400041210006900115260000800184300001400192490000700206520129100213100002401504700001801528700001901546700002001565856010601585 2017 eng d00aSupramolecular synthons in bumetanide cocrystals and ternary products0 aSupramolecular synthons in bumetanide cocrystals and ternary pro cAUG a4225-42360 v173 aA novel design strategy for cocrystals of the diuretic sulfonamide drug bumetanide (BUM) with carboxamides is reported based on reliable supramolecular synthons. Binary cocrystals of BUM with pyridine carboxamides, pyridones, and cytosine were obtained by solvent assisted grinding followed by solution crystallization. All cocrystal structures exhibit hydrogen bonding of the coformer with the carboxylic acid group of BUM via heterosynthons which replace the acid homodimer in the drug crystal structure. Pyridones are inserted as N-H center dot center dot center dot O dimers which are in turn bonded to the acid group of BUM, while the pyridine amide coformers interact via the acid amide heterosynthon. Cocrystal polymorphs were obtained for bumetanide isonicotinamide cocrystal structure with the sulfonamide pyridine and sulfonamide acid synthons. Careful crystal packing analysis of BUM structure and nine new binary adducts gave an idea for the design ternary cocrystals, and subsequently four new ternary crystalline products were crystallized. Whereas the binary cocrystal structures were confirmed by single crystal diffraction, the ternary combinations were chatacterized by their unique powder X-ray diffraction patterns as well as by thermal and spectroscopic techniques.1 aAllu, Suryanarayana1 aBolla, Geetha1 aTothadi, Srinu1 aNangia, Ashwini uhttps://library.ncl.res.in/content/supramolecular-synthons-bumetanide-cocrystals-and-ternary-products02362nas a2200181 4500008004100000022001500041245013900056210006900195260000800264300001200272490000600284520167300290100002101963700001901984700002602003700002002029856013102049 2018 eng d a 2052-252500a Systematic synthesis of a 6-component organic-salt alloy of naftopidil, and pentanary, quaternary and ternary multicomponent crystals0 aSystematic synthesis of a 6component organicsalt alloy of naftop cNOV a816-8220 v53 aThe single-crystal X-ray structure of a 6-component organic-salt alloy (hexanary) of naftopidil (1) (an active pharmaceutical ingredient) with benzoic acid (2) and four different hydroxy-substituted benzoic acids, i.e. salicylic acid (3), 2,3-dihydroxybenzoic acid (4), 2,4-dihydroxybenzoic acid (5) and 2,6-dihydroxybenzoic acid (6), is reported. The hexanary assembly originates from the observation that the binary salts of naftopidil with the above acids are isostructural. In addition to the 6-component solid, we also describe five 5-component, ten 4-component, and ten 3-component organic-salt alloys of naftopidil (1) with carboxylic acids (2)-(6). These alloys were obtained from different combinations of the acids with the drug. The synthetic design of the multicomponent organic alloys is based on the rationale of geometrical factors (shape and size) and chemical interactions (hydrogen bonds). The common supramolecular synthon in all these crystal structures was the cyclic N+ - H center dot center dot center dot O- and O-H center dot center dot center dot O hydrogen-bonded motif of R-2(2) (9) graph set between the 2-hydroxyammonium group of naftopidil and the carboxylate anion. This ionic synthon is strong and robust, directing the isostructural assembly of naftopidil with up to five different carboxylic acids in the crystal structure together with the lower-level multicomponent adducts. Solution crystallization by slow evaporation provided the multicomponent organic salts and alloys which were characterized by a combination of single-crystal X-ray diffraction, powder X-ray diffraction, NMR and differential scanning calorimetry techniques.1 aDandela, Rambabu1 aTothadi, Srinu1 aMarelli, Udaya, Kiran1 aNangia, Ashwini uhttps://library.ncl.res.in/content/systematic-synthesis-6-component-organic-salt-alloy-naftopidil-and-pentanary-quaternary-and01624nas a2200241 4500008004100000022001400041245009900055210006900154260000800223520080700231653001901038653003601057653001301093653002501106653001801131100001701149700001501166700001901181700001801200700001901218700001901237856012601256 2019 eng d a0947-653900aSaturated N-heterocyclic carbene based thiele's hydrocarbon with a tetrafluorophenylene linker0 aSaturated Nheterocyclic carbene based thieles hydrocarbon with a cNOV3 a

The synthesis of a SIPr [1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene] derived Kekule diradicaloid with a tetrafluorophenylene spacer (3) has been described. Two synthetic routes have been reported to access 3. The cleavage of C-F bond of C6F6 by SIPr in the presence of BF3 led to double C-F activated compound with two tetrafluoro borate counter anions (2), which upon reduction by lithium metal afforded 3. Alternatively, 3 can be directly accessed in one step by reacting SIPr with C6F6 in presence of Mg metal. Compounds 2 and 3 were well characterized spectroscopically and by single-crystal X-ray diffraction studies. Experimental and computational studies support the cumulenic closed-shell singlet state of 3 with a singlet-triplet energy gap (Delta ES-T) of 23.7 kcal mol(-1).

10aC-F activation10aDensity functional calculations10afluorine10aKekule diradicaloids10asaturated NHC1 aKundu, Gargi1 aDe, Sriman1 aTothadi, Srinu1 aDas, Abhishek1 aKoley, Debasis1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/saturated-n-heterocyclic-carbene-based-thieles-hydrocarbon-tetrafluorophenylene-linker01510nas a2200181 4500008004100000022001400041245011800055210006900173260000800242300001400250490000700264520085000271100001701121700002001138700001901158700001901177856013201196 2020 eng d a0276-733300aStepwise nucleophilic substitution to access saturated N-heterocyclic carbene haloboranes with boron-methyl bonds0 aStepwise nucleophilic substitution to access saturated Nheterocy cDEC a4696-47030 v393 a

Compounds of boranes with N-heterocyclic carbenes are known, yet little attention has been paid to NHC compounds of boron bearing methyl and halogen moieties together. The reason can be attributed to the hazardous methyldichloroborane (MeBCl2), which ignites in air. We describe here convenient solution-phase access to SIDipp.MeBCl2 (SIDipp = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) (3) by a salt metathesis reaction of SIDipp.BCl3 (2) with MeLi. Replacement of the chlorine atoms of 3 with stepwise addition of AgOTf led to the formation of SIDipp.MeBCl(OTf) (4) and SIDipp.MeB(OTf)2 (5). In the case of 4, all of the substituents on the boron atom are different. Subsequently, we extended our synthetic approach to the amidinate system and prepared PhC(NtBu)2B(Me)Cl (7) from the reaction of PhC(NtBu)2BCl2 (6) with MeLi.

1 aKundu, Gargi1 aPahar, Sanjukta1 aTothadi, Srinu1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/stepwise-nucleophilic-substitution-access-saturated-n-heterocyclic-carbene-haloboranes-boron01087nas a2200193 4500008004100000245008900041210006900130260000800199300001400207490000700221520042400228100002600652700002200678700002100700700001900721700002000740700002100760856011200781 2021 eng d00aSeparation of a diastereomeric diol pair using the mechanical properties of crystals0 aSeparation of a diastereomeric diol pair using the mechanical pr cOCT a7056-70600 v233 aWe report the separation of a (2S,3R/S)-3-ethyl-1-phenylhex-5-ene-2,3-diol (ephd) diastereomeric pair with visually indistinguishable acicular morphologies based on their mechanical responses, which is found to be more efficient than conventional separation methods. Furthermore, the molecular crystals of (2S,3R)-ephd show elastic deformation, while (2S,3S)-ephd fractures in a brittle manner under similar conditions.1 aGamidi, Rama, Krishna1 aDandawate, Monica1 aChoudhury, Rahul1 aTothadi, Srinu1 aNangia, Ashwini1 aReddy, Srinivasa uhttps://library.ncl.res.in/content/separation-diastereomeric-diol-pair-using-mechanical-properties-crystals01710nas a2200253 4500008004100000022001400041245008100055210006900136260000900205300001100214490000900225520089000234653002701124653001501151653001701166653002601183100002601209700002001235700001901255700001801274700003001292700002101322856011301343 2021 eng d a0022-286000aStructure-property correlation of halogen substituted benzothiazole crystals0 aStructureproperty correlation of halogen substituted benzothiazo cNOV  a1307650 v12433 aWe have synthesized 3 benzothiazole crystals (1-3) based on existing knowledge of combining flexibility and optical properties towards achieving applications for flexible optoelectronics. However, one crystal was found to be elastically bendable and was found to comply necessary packing features for elasticity. Other two crystals do not obey packing features for elasticity hence they are brittle in nature. Further, Hirshfeld analysis illustrates that elastic crystal 1 possess more number of weak and dispersive interactions compared to other crystals. These interactions were instrumental in invoking elasticity. Moreover, crystals 1-3 were found to be fluorescent as well at specific excitation wavelengths. Therefore, among these crystals, particularly crystal 1 is considered as more promising candidate for flexible optoelectronics. (C) 2021 Elsevier B.V. All rights reserved.10aBenzothiazole crystals10aElasticity10aHalogen bond10amechanical properties1 aThekkeppat, Nipun, P.1 aSingla, Labhini1 aTothadi, Srinu1 aDas, Priyadip1 aChoudhury, Angshuman, Roy1 aGhosh, Soumyajit uhttps://library.ncl.res.in/content/structure-property-correlation-halogen-substituted-benzothiazole-crystals01160nas a2200205 4500008004100000022001400041245009900055210006900154260000900223300001400232490000700246520044700253100002000700700001900720700001900739700002200758700002700780700001800807856012900825 2021 eng d a0276-733300aSynthesis and application of silylene-stabilized low-coordinate Ag(I)-arene cationic complexes0 aSynthesis and application of silylenestabilized lowcoordinate Ag cJUN  a1626-16320 v403 aWe report the first examples of N-heterocyclic silylene-stabilized monocoordinate Ag(I) cationic complexes weakly bound to the free arene rings (C6H6, C6Me6, and C7H8). Further, the application of these electrophilic Ag(I) complexes as catalysts has been investigated toward A(3)-coupling reactions, which afforded a series of propargylamines in good to excellent yields with low catalyst loading under a solvent-free condition (19 examples).1 aParvin, Nasrina1 aSen, Nilanjana1 aTothadi, Srinu1 aMuhammed, Shahila1 aParameswaran, Pattiyil1 aKhan, Shabana uhttps://library.ncl.res.in/content/synthesis-and-application-silylene-stabilized-low-coordinate-agi-arene-cationic-complexes01587nas a2200181 4500008004100000022001400041245010900055210006900164260000800233300001600241490000700257520093700264100001701201700001901218700001901237700001901256856013001275 2022 eng d a0020-166900aSix-membered saturated NHC-stabilized borenium cations: isolation of a cationic analogue of borinic acid0 aSixmembered saturated NHCstabilized borenium cations isolation o cAUG a12991-129970 v613 a

The reaction of six-membered saturated NHC [1,3-di(2,6-diisopropylphenyl) tetrahydropyrimidine-2-ylidene; henceforth abbreviated as 6-SIDipp] with PhBCl2 yields a Lewis base adduct, 6-SIDipp.PhBCl2 (1), which readily undergoes nucleophilic substitution reaction with AgNO3, leading to the single (2) and double (3) substitution of both chlorides with ONO2 moieties at the boron atom. The reaction of 1 with 1 equiv of AlCl3 resulted in a borenium cation of composition [6-SIDipp.B(Ph)Cl]+ (4) with AlCl4- as the counteranion. Although borenium cations with different substituents on boron have been reported, a structurally characterized phenylchloroborenium cation remains unknown. Similarly, the reaction of 1 with triflic acid provides the first representative of a new class of borenium cations bearing one hydroxyl and one phenyl group on boron (5), a cationic analogue of borinic acid. Ph-BN H Diphenylborinic acid

1 aKundu, Gargi1 aBalayan, Kajal1 aTothadi, Srinu1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/six-membered-saturated-nhc-stabilized-borenium-cations-isolation-cationic-analogue-borinic01271nas a2200205 4500008004100000022001400041245011800055210006900173260000900242300001400251490000700265520055300272100001700825700002300842700001500865700001700880700001900897700001900916856013000935 2022 eng d a1359-734500aSubstitution at sp(3) boron of a six-membered NHC center dot BH3: convenient access to a dihydroxyborenium cation0 aSubstitution at sp3 boron of a sixmembered NHC center dot BH3 co cMAR  a3783-37860 v583 a

Herein, we have undertaken the synthesis and investigated the reactivity of a 6-membered saturated NHC borane adduct (1). Direct electrophilic halogenation of 1 with a stoichiometric amount of I-2 led to NHC boryl iodides, 6-SIDipp center dot BH2I (2) and 6-SIDipp center dot BHI2 (3), which were further reacted with various nucleophiles to give novel 6-SIDipp based mono and disubstituted boranes with OTf (4 and 6) or ONO2 (5 and 7) functional groups. The addition of Br-2/H2O to 1 smoothly results in a dihydroxyborenium cation (8).

1 aKundu, Gargi1 aAjithkumar, V., S.1 aRaj, Vipin1 aVanka, Kumar1 aTothadi, Srinu1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/substitution-sp3-boron-six-membered-nhc-center-dot-bh3-convenient-access-dihydroxyborenium01712nas a2200253 4500008004100000022001400041245005700055210005600112260000800168300001500176490000700191520099700198653001701195653000801212653002201220653000901242100001801251700001701269700002501286700001701311700001901328700001901347856009201366 2023 eng d a1434-194800aSix-membered NHC stabilized monomeric zinc complexes0 aSixmembered NHC stabilized monomeric zinc complexes cJUL ae2023001670 v263 a

This paper describes the rare use of a 6-membered saturated N-heterocyclic carbene (NHC) known as 1,3-di(2,6-diisopropylphenyl) tetrahydropyrimidine-2-ylidene (abbreviated as 6-SI-Dipp) as a ligand in zinc chemistry. We report on the investigation of the reactions between 6-SI-Dipp and ZnX2, which resulted in a range of new monomeric 6-SIDipp center dot ZnX2 complexes (X=Et (1), Cl (2), Br (3), and I (4)). We also prepared a new NHC zinc complex where the two substituents of the zinc atom are different, 6-SIDipp center dot Zn(Et)Br (7) through the reaction of the proligand [6-SIDippH]Br with ZnEt2. We have observed that the reactions of complex 1 with sulfur and HBpin led to the removal of the ZnEt2 moiety, resulting in the formation of a C=S double bond and a B H activation product, respectively. Lastly, the reaction of 1 with five-membered NHCs led to the exchange of carbene and the formation of either 5-IDipp center dot ZnEt2 (8) or 5-SIDipp center dot ZnEt2 (9).

10aLewis adduct10aNHC10aX-ray diffraction10azinc1 aGour, Kritika1 aKundu, Gargi1 aDash, Soumya, Ranjan1 aVanka, Kumar1 aTothadi, Srinu1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/six-membered-nhc-stabilized-monomeric-zinc-complexes00708nas a2200205 4500008004100000022001400041245010500055210006900160260000900229300001400238490000700252653001500259653001300274653001400287100001700301700002000318700001900338700001900357856012600376 2024 eng d a0276-733300aSaturated NHC-stabilized borenium, boronium, hydride-bridged boron cations, and a bora-acyl chloride0 aSaturated NHCstabilized borenium boronium hydridebridged boron c cJUN  a1355-13610 v4310aactivation10aBORINIUM10aChemistry1 aKundu, Gargi1 aAmrutha, P., R.1 aTothadi, Srinu1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/saturated-nhc-stabilized-borenium-boronium-hydride-bridged-boron-cations-and-bora-acyl03455nas a2200169 4500008004100000245010400041210006900145260000800214300001200222490000700234520282900241100001703070700001903087700002403106700001503130856014003145 2024 eng d00aSynthesis, characterization, and crystal structure of 2-(2-azido­phen­yl)-3-oxo-3H-indole 1-oxide0 aSynthesis characterization and crystal structure of 22azido phen cMAR a310-3130 v803 a
An attempt to explore the reactivity of the nitro group in the presence of gold catalysis in comparison to the azide group yielded intriguing results. Surprisingly, only the nitro group exhibited reactivity, ultimately giving rise to the formation of the title isatogen.
An attempt to explore the reactivity of the nitro group in the presence of gold catalysis in comparison to the azide group yielded intriguing results. Surprisingly, only the nitro group exhibited reactivity, ultimately giving rise to the formation of the title isatogen, C14H8N4O2. In the crystal structure, weak C—H⋯O hydrogen bonds and π–π stacking inter­actions link the mol­ecules. The structure exhibits disorder of the mol­ecule.

 

1 aDhote, Pawan1 aTothadi, Srinu1 aRamana, Chepuri, V.1 aChopra, D. uhttps://library.ncl.res.in/content/synthesis-characterization-and-crystal-structure-2-2-azido%C2%ADphen%C2%ADyl-3-oxo-3h-indole-1-oxide