01916nas a2200193   4500008004100000245010800041210006900149260000800218300001400226490000700240520121800247100001701465700002401482700002001506700002301526700002801549700002501577856012001602       2018                        eng d00aSoluble polybenzimidazoles with intrinsic porosity: synthesis, structure, properties and processability0 aSoluble polybenzimidazoles with intrinsic porosity synthesis str  cMAY  a1046-10570 v563 aWe have explored two novel comonomers, namely, 4,16-dicarboxyl[2.2]paracyclophane and 5,5,6,6-tetraamino-3,3,3,3-tetramethyl-1,1-spirobi[indane], for the synthesis of co-polybenzimidazoles (co-PBIs) with intrinsic porosity. Both these monomers possess twisted structures that can lead to awkward macromolecular shapes that cannot pack efficiently. The consequences of introducing these two monomers on the structure and properties of PBIs are reported. The random copolymers synthesized are amorphous and possess glass transition temperatures (T(g)s) greater than 400 degrees C. T-g decreases with increasing comonomer content indicating an increase in fractional free volume. The copolymers have low surface area. TEM and BET measurements show evidence of mesopore formation. The copolymers show significant carbon dioxide adsorption. Single chain molecular dynamics simulation of 24-mer repeat units shows intramolecular void spaces arising as a result of distorted polymer chain with reduced conformational mobility. These studies define a new synthetic strategy for bottoms-up synthesis of PBIs with intrinsic porosity. (c) 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1046-10571 aKumar, Vikas1 aChatterjee, Shyambo1 aSharma, Pragati1 aChakrabarty, Suman1 aAvadhani, Chilukuri, V.1 aSivaram, Swaminathan  uhttps://library.ncl.res.in/content/soluble-polybenzimidazoles-intrinsic-porosity-synthesis-structure-properties-and01528nas a2200217   4500008004100000022001400041245012200055210006900177260000900246300001400255490000700269520076700276100001901043700002301062700001901085700001701104700001601121700002401137700002201161856012701183       2019                        eng d  a1477-922600aStabilization of bis(chlorogermyliumylidene)s within bifunctional PNNP ligand frameworks and their reactivity studies0 aStabilization of bischlorogermyliumylidenes within bifunctional   cJUN   a7344-73510 v483 a<p>The diiminodiphosphine (L-im) and diaminodiphosphines (l-NH and l-NMe) with a bifunctional PNNP ligand framework have been employed to host two [GeCl](+) units leading to the formation of bis(chlorogermyliumylidene) 1-3, respectively. The synthetic route involves a 1:2 stoichiometric reaction between the PNNP ligand and GeCl(2)dioxane and the subsequent addition of two equivalents of chloride abstracting agent. Compound 1 is unstable towards coordinating solvents and Lewis bases, resulting in the displacement of the GeCl unit and the formation of rearranged products 4 and 5. However, the diaminodiphosphine coordinated Ge(ii) bis(monocation)s 2 and 3 proved to be stable and revealed their electrophilic behaviour towards the Lewis bases studied.</p>
1 aSahoo, Padmini1 aRaut, Ravindra, K.1 aMaurya, Devesh1 aKumar, Vikas1 aRani, Pooja1 aGonnade, Rajesh, G.1 aMajumdar, Moumita  uhttps://library.ncl.res.in/content/stabilization-bischlorogermyliumylidenes-within-bifunctional-pnnp-ligand-frameworks-and01877nas a2200241   4500008004100000022001400041245010600055210006900161260000800230300001600238490000700254520106200261653002301323653002301346653002001369653002201389653001401411100001701425700002401442700002001466700002201486856012701508       2021                        eng d  a1433-785100aStabilization of the elusive antimony(I) cation and its coordination complexes with transition metals0 aStabilization of the elusive antimonyI cation and its coordinati  cNOV  a25522-255290 v603 aUpon stabilization by 5,6-bis(diisopropylphosphino)acenaphthene to form compound 1, the fugitive antimony (I) cation exhibited nucleophilic behavior towards coinage metals. Compound 1 was strategically synthesized at room temperature from SbCl3, the bis(phosphine), and trimethylsilyl trifluoromethanesulfonate taken in a 1:2:3 ratio, whereby the bis(phosphine) plays the dual role of a reductant and a supporting ligand. The generation of 1 involves two-electron oxidation of the ligand to form a P-P bonded diphosphonium dication. Compound 1 was separated from this dication to give both products in pure form in moderate yields. Despite the overall positive charge, the Sb-I site in 1 was found to bind to metal centers, forming complexes with Au-I, Ag-I and Cu-I. Compound 1 reduced Cu-II to Cu-I and formed a coordination complex with the resulting Cu-I species. The effects of the electron-rich bis(phosphine) and the constrained peri geometry in stabilizing and enhancing the nucleophilicity of 1 have been rationalized through computational studies.10aantimony(I) cation10acoordination modes10anucleophilicity10aphosphine ligands10areduction1 aKumar, Vikas1 aGonnade, Rajesh, G.1 aYildiz, Cem, B.1 aMajumdar, Moumita  uhttps://library.ncl.res.in/content/stabilization-elusive-antimonyi-cation-and-its-coordination-complexes-transition-metals