Vipin Raj KJawaharlal Nehru Centre for Advanced Scientific Research | JNCASR · Theoretical Sciences Unit
Vipin Raj K
Doctor of Philosophy
About
21
Publications
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Introduction
I am a computational chemist who seeks insights (and possibly predict!) into various chemical reactions using the principles of quantum chemistry, thermodynamics, and chemical kinetics.
My research interest is in computational studies into heterogeneous Ziegler-Natta catalysis, mainly focused on Lewis base donors' various roles in the system. Furthermore, I also frequently collaborate with experimental colleagues to study various homogeneous catalysis reactions and bonding studies.
Additional affiliations
August 2017 - April 2019
August 2015 - August 2017
Education
August 2018 - March 2023
July 2011 - July 2013
June 2009 - June 2011
Publications
Publications (21)
Developing donors for Ziegler‐Natta (ZN) catalysis to control the polymerization reaction and produce polymers with desirable properties has always been challenging due to the multi‐component nature of the catalytic systems. Here, we have developed a new synthetic protocol for making two external donors, D1 (2,2,2‐trifluoroethyl myristate) and D2 (...
This article focuses on the different components that make up Ziegler–Natta olefin polymerization systems and shows how investigating the interactions between these components through computational approaches provide crucial information about the chemistry of these systems. Hence, the necessity of theory acting as a counterpoint to experiment is re...
Earth abundant, first row transition metals offer a cheap and sustainable alternative to the rare and precious metals. However, utilization of first row metals in catalysis requires harsh reaction conditions, suffers from limited activity, and fails to tolerate functional groups. Reported here is a highly efficient iron catalyzed hydroformylation o...
Gold-catalysis, in this century, is one of the most emerging and promising new areas of research in organic synthesis. During the last two decades, a wide range of distinct synthetic methodologies have been unveiled employing homogeneous gold catalysis and aptly applied in the synthesis of numerous natural products and biologically active molecules...
![³¹P NMR spectrum of [(L1)(COD)Rh(BF4)] in CDCl3.](publication/357023119/figure/fig4/AS:11431281244360982@1715917420414/P-NMR-spectrum-of-L1CODRhBF4-in-CDCl3_Q320.jpg)
Although hybrid bidentate ligands are known to yield highly enantioselective products in asymmetric hydrogenation (AH), synthesis of these ligands is an arduous process. Herein, a one pot, atom‐economic synthesis of a hybrid phosphine‐phosphite (L1) is reported. After understanding the reactivity difference between an O‐nucleophile versus C‐nucleop...
The significance of small molecule activation spans diverse fields, including catalysis, medicine, and energy production. This article delves into the chemistry of low‐valent group 13 and 14 compounds as a more sustainable alternative for small molecule activation compared to the often toxic and expensive transition metal compounds. Emphasizing the...
Although hybrid bidentate ligands are known to yield highly enantioselective products in asymmetric hydrogenation (AH), synthesis of these ligands is an arduous process. Herein, a one pot, atom-economic synthesis of a hybrid phosphine-phosphite (L1) is reported. After understanding the reactivity difference between an O-nucleophile versus C-nucleop...
The reaction of a nickel(II) chloride complex containing a tridentate β‐diketiminato ligand with a picolyl group [2,6‐iPr2‐C6H3NC(Me)CHC(Me)NH(CH2py)]Ni(II)Cl (1)] with KSi(SiMe3)3 conveniently afforded a nickel(I) radical with a T‐shaped geometry (2). The compound‘s metalloradical nature was confirmed through electron paramagnetic resonance (EPR)...
In the last decade, magnesium complexes have emerged as a viable alternative to transition‐metal catalysts for the hydrofunctionalization of unsaturated bonds. However, their potential for advanced catalytic reactions has not been thoroughly investigated. To address this gap, we have developed a novel magnesium amide compound (3) using a PNP framew...
This study investigates the reactivity of a hypersilyl germylene [PhC(NtBu)2GeSi(SiMe3)3] (1) with various organic compounds including azides, diazoalkanes, 1,2-diphenylhydrazine, and trifluoroacetophenone. The reactivity observed in these reactions is driven by the insertion of the organic fragment between a silicon and germanium bond. This leads...
Despite recent advancements in the chemistry of multiply bound boron compounds, the laboratory isolation of the parent oxoborane moiety, HBO has long remained an unsolved and well-recognized challenge. The reaction of 6-SIDipp·BH3 [6-SIDipp = 1,3-di(2,6-diisopropylphenyl)tetrahydropyrimidine-2-ylidene] with GaCl3 afforded an unusual boron-gallium 3...
Ziegler–Natta (Z–N) systems have been well established as heterogeneous catalysts that produce isotactic polypropylene and polyethylene with great efficiency. Such systems benefit considerably from donors (Lewis bases), whose addition significantly improves the stereoselectivity of polymerization. There is a consensus that the primary role of the e...
The reaction of PhC(NtBu)2SiSi(SiMe3)3 (1) with Me3SiCH2Cl afforded an unsymmetrical sp2-sp3 disilene, 2 with concomitant elimination of Me3SiCl. Analogous reaction with PhC(NtBu)2SiCl resulted in the oxidative addition of the C–Cl...
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 I2 led to NHC boryl iodides, 6-SIDipp·BH2I (2) and 6-SIDipp·BHI2 (3), which were further reacted with various nucleophiles to give novel 6-SIDipp based mono...
Retrieval of depleting resources from wastewater could resolve its mounting demands in our society. Phosphate is an essential nutrient for all living things. However, the diminution of global reserves of...
The recently reported hypersilylsilylene PhC(NtBu)2SiSi(SiMe3)3 (1) reacts with BH3, 9-BBN, and PhBCl2 to yield the respective Lewis acid base adducts 2–4, respectively. Compound 4 undergoes isomerization to form a ring expansion product 5. The same silylene was found to initially form an adduct with HBpin (6) and subsequently isomerized to 7 via t...
Despite the explosive growth of germylene compounds as ligands in transition metal complexes, there is a modicum of precedence for the germylene zinc complexes. In this work, the synthesis and characterization of new germylene zinc complexes [PhC(NtBu)2Ge{N(SiMe3)2}→ZnX2]2 (X= Br (2) and I (3)) supported by (benz)‐amidinato germylene ligands are re...
Proton-exchange membrane fuel cells are promising energy devices for sustainable future due to green features, high power density, and mild operating conditions. A facile proton-conducting membrane plays a pivotal role to boost the efficiency of fuel cells and hence focused research in this area is highly desirable. Major issues associated with the...
The addition of HBpin to PhC(NtBu)2SiN(SiMe3)2 (1) results in the cleavage of the B‒H bond in a cooperative fashion across the Si and amidinate-C sites. The reactions of 1 with...
Despite the remarkable ability of N-heterocyclic silylene to act as a Lewis base and form stable Lewis adducts with group 13 elements such as boron, aluminum, and gallium, there has been no such comparable investigation with indium and the realization of a stable silylene–indium complex has still remained elusive. Similarly, a germylene–indium comp...
Silylene [PhC(NtBu)2SiN(SiMe3)2] (1) activates the C(sp3)-H and C-F bond of acetophenone and 1,1,1 trifluoroacetophenone, respectively under mild conditions. The reaction is initiated via nucleophilic attack from the oxygen to the...
Questions
Questions (5)
I have a system with an MgCl2 surface on which various molecules like TiCl4, phthalate, succinate, and alkyl aluminum species are coordinated. I want to do a conformational analysis of the 'R' group present in the succinate. For example, in one case, there are two cyclopentyl groups present in the system. How these two cyclopentyl groups are oriented towards TiCl4 in the structure is of chemical importance.
I have tried HyperChem software to do a conformational analysis. However, the problem is that the entire MgCl2 surface is distorted. On the other hand, if I manually change the dihedral angle and create many conformations and do optimization using Turbomole 7.0 software, it is time-consuming.
Is there any software available to do the conformational analysis of the relevant part of an extensive system? By fixing other parts or by any means?
Thanks in advance!
I want to study the effect of the n-hexane solvent in the Ziegler-Natta polymerization reaction. Since the reaction is performed in the slurry phase, I guess there is no need to use the COSMO model (implicit solvent model). Is it okay to use an explicit solvent model (use one solvent molecule explicitly) without using the COSMO to study the effect of n-hexane in the reaction?
