01458nas a2200217 4500008004100000022001400041245013200055210006900187260007500256300001400331490000600345520063000351653001200981653002000993653002101013653001801034653001201052100002201064700002401086856013001110 2015 eng d a1867-388000aHighly regioselective isomerizing hydroformylation of long-chain internal olefins catalyzed by a rhodium bis(phosphite) complex0 aHighly regioselective isomerizing hydroformylation of longchain  aPOSTFACH 101161, 69451 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcNOV a3468-34710 v73 a

The single-step synthesis, coordination behavior, and application of a bis(phosphite) ligand in the isomerizing hydroformylation of internal olefins was investigated. Interestingly, high-pressure NMR spectroscopy investigations revealed unexpected inequivalency of the two phosphorus nuclei, which display bisequatorial coordination of the bis(phosphite) ligand in a trigonal bipyramidal rhodium complex. Upon employment in the isomerizing hydroformylation of the exceedingly challenging plant oil derived substrate methyl oleate, the bis(phosphite) rhodium complex revealed an unprecedented linear selectivity of 75%.

10aalkenes10abis(phosphite)s10aHydroformylation10aisomerization10aRhodium1 aPandey, Swechchha1 aChikkali, Samir, H. uhttps://library.ncl.res.in/content/highly-regioselective-isomerizing-hydroformylation-long-chain-internal-olefins-catalyzed-001819nas a2200217 4500008004100000022001400041245008100055210006900136260000800205520109100213653002601304653002101330653001801351653001201369653002301381100001901404700001701423700002701440700002401467856011001491 2021 eng d a1527-899900aPhosphorus ligands in hydroformylation and hydrogenation: a personal account0 aPhosphorus ligands in hydroformylation and hydrogenation a perso cMAR3 a

Metal-catalyzed hydroformylation and hydrogenation heavily rely on ligands, among which phosphorous ligands play a pivotal role. This personal account presents a selection of three distinct classes of phosphorous ligands, namely, monodentate meta-substituted phosphinites, bis-phosphites, and P-chiral supramolecular phosphines, developed in our group. The synthesis of these ligands, isolation, characterization, and their performance in transition metal-catalyzed hydroformylation, isomerizing hydroformylation, and asymmetric hydrogenation of olefins is summarized. The state of the art development in iron-catalyzed hydroformylation of alkenes and our contributions to the field is discussed. Use of phosphines enabled iron-catalyzed hydroformylation of alkenes under mild conditions. Thus, this account demonstrates the central role of phosphorus ligands in industrially relevant transformations such as hydrogenation and hydroformylation. The seemingly matured field of ligand discovery still holds significant potential and will steer the field of homogeneous catalysis.

10aHomogeneous catalysis10aHydroformylation10aHydrogenation10aOlefins10aPhosphorus ligands1 aTewari, Tanuja1 aKumar, Rohit1 aChandanshive, Amol, C.1 aChikkali, Samir, H. uhttps://library.ncl.res.in/content/phosphorus-ligands-hydroformylation-and-hydrogenation-personal-account01991nas a2200217 4500008004100000022001400041245006100055210006100116260000800177300001100185490000800196520135900204653001401563653001201577653001401589653002101603653002301624100001701647700002401664856008501688 2022 eng d a0022-328X00aHydroformylation of olefins by metals other than rhodium0 aHydroformylation of olefins by metals other than rhodium cFEB a1222310 v9603 aMetal catalyzed hydroformylation of alkenes is an atom economic transformation to construct useful aldehydes and is being industrially practiced for decades. The most commonly used metal for this transformation on an industrial scale is rhodium. However, rhodium is rare, costly, and is depleting at a skyrocketing rate. Therefore, finding a suitable alternative to rhodium for metal-catalyzed hydroformylation has been on the radar of many academic and industrial researchers. This review presents the scientific advancements reported in the hydroformylation reaction using metals other than rhodium. An overview of recent progress in palladium, iridium, ruthenium, cobalt, platinum, and iron-catalyzed hydroformylation is presented. Hydroformylation of alkenes and alkynes, using syngas as well as syngas surrogates is examined. The evaluation of the current status of non-rhodium metals in hydroformylation suggests that the field is still in a nascent stage and, except cobalt, no other metal poses a significant challenge to the dominance of rhodium. Deep mechanistic understanding of rate-limiting elementary steps in the non-rhodium metals is largely missing and thus only limited success is reported. Intense research on ligand design, mechanistic understanding, and choice of non-rhodium metal precursors may change this scenario in near future.10aaldehydes10aalkenes10acatalysis10aHydroformylation10aNon-rhodium metals1 aKumar, Rohit1 aChikkali, Samir, H. uhttps://library.ncl.res.in/content/hydroformylation-olefins-metals-other-rhodium02224nas a2200253 4500008004100000022001400041245010100055210006900156260000800225300001100233490000800244520136700252653002401619653003201643653002201675653002901697653002101726653001801747100002101765700001901786700002401805700001701829856012401846 2023 eng d a0022-328X00aComputational insights into the iron-catalyze d magnesium-me diate d hydroformylation of alkynes0 aComputational insights into the ironcatalyze d magnesiumme diate cFEB a1226210 v9863 a

Iron is one of the most abundant transition metals in the earth's crust. It has attracted a lot of attention due to its low toxicity, bio-compatibility, and high natural abundance. Iron-catalyzed hydroamination, hydroalkoxylation, hydrocarboxylation, hydrosilylation, hydroboration, hydrophosphination, hydromagnesiation, and carbonylation reactions have therefore been developed over the past decades. However, despite many experimental and theoretical studies, a complete mechanistic understanding of iron-catalyzed hydrofunctionalisation at the molecular level has not yet been achieved. In this work, through density functional theory (DFT) calculations, we have shown the most feasible path for the hydroformylation of alkynes for an experimentally studied system. We have looked at the iron salt as a precatalyst without any external donor ligand, and the calculations revealed that hydrometalation followed by beta-hydride elimination was favorable over the direct migration of the beta-hydrogen to carbon. Furthermore, our calculations show that the solvent plays an important role in the hydromagnesiation reaction. Furthermore, we have employed an explicit solvent model, where the attachment of one molecule of solvent to the iron center was seen to stabilize the transition states significantly.(c) 2023 Elsevier B.V. All rights reserved.

10aComputational study10aEthylene Assisted Catalysis10aEtMgBr Assistance10aExplicit Role of Solvent10aHydroformylation10aIron Catalyst1 aSharma, Himanshu1 aTewari, Tanuja1 aChikkali, Samir, H.1 aVanka, Kumar uhttps://library.ncl.res.in/content/computational-insights-iron-catalyze-d-magnesium-me-diate-d-hydroformylation-alkynes01926nas a2200217 4500008004100000022001400041245008500055210006900140260000900209490000700218520122800225653001401453653001201467653001201479653002101491653001901512100001901531700001701550700002401567856011701591 2023 eng d a1867-388000aIron-catalyzed magnesium-mediated formal hydroformylation of alkynes and alkenes0 aIroncatalyzed magnesiummediated formal hydroformylation of alkyn cFEB 0 v153 a

Alkynes and alkenes are routinely converted to corresponding synthetically versatile aldehydes using rhodium-catalyzed hydroformylation. However, rhodium is rare, precious, costly, and depleting at a considerably high rate. Reported here is iron-catalyzed, magnesium-mediated, formal hydroformylation of alkynes and alkenes in the absence of syngas. Readily available FeCl2 in the presence of alkyl magnesium halide, and dimethyl formamide, catalyzes hydroformylation of various alkynes and selectively produces alpha,beta-unsaturated aldehydes in good to excellent conversion. Mechanistic investigations revealed the presence of vinyl magnesium intermediate, the kinetic study disclosed the first-order dependence of the reaction on iron loading, and the control experiment authenticated the iron catalyst's homogeneous nature. The scope of this methodology was amplified, and 20 alkenes were examined. [Fe(acac)(3)] in the presence of ligand, alkyl magnesium halide, and dimethyl formamide catalyzed the hydroformylation of alkenes and displayed good to excellent conversion. An earth-abundant iron catalyst offering a syngas cylinder-free safe alternative to high-pressure hydroformylation has been reported.

10aaldehydes10aalkenes10aAlkynes10aHydroformylation10airon catalysis1 aTewari, Tanuja1 aKumar, Rohit1 aChikkali, Samir, H. uhttps://library.ncl.res.in/content/iron-catalyzed-magnesium-mediated-formal-hydroformylation-alkynes-and-alkenes01984nas a2200229 4500008004100000022001400041245008100055210006900136260000900205300000800214490000800222520124900230653001401479653001701493653002101510653003101531653002101562100001701583700001701600700002401617856011301641 2023 eng d a0974-362600aRh-catalyzed asymmetric hydroformylation of olefins using phosphorus ligands0 aRhcatalyzed asymmetric hydroformylation of olefins using phospho cNOV  a1080 v1353 a

Easily accessible BINOL-based monodentate phosphite ligand L1 and hybrid ligand L2 have been synthesized in good yield by following a one-pot, two-step protocol. A single 31P resonance at 146.6 ppm confirmed the formation of L1. Subsequent 1-2D NMR and mass spectrometric analysis authenticated the existence of L1. These ligands afforded excellent activity and regio-selectivity in the Rh-catalyzed AHF of styrenic substrates. L1 showed excellent regioselectivity but did not discriminate between the two enantiomers, while L2 displayed an enantiomeric excess (ee) of up to 20%. In our attempts to understand the reasons for low ee, the coordination behavior of L2 was investigated. The coordination study revealed that L2 coordinates with the Rh as a monodentate ligand, although there are two P-sites. It was found that only the phosphine arm was coordinated to the Rh and the phosphite arm stayed away from the Rh core at the ambient temperature, leading to moderate ee.Graphical abstractOne-step synthesis of a phosphite (L1) and a phosphine-phosphite (L2) ligand and their implication in the asymmetric hydroformylation of olefins with excellent regioselectivity (>95%) and moderate enantioselectivity (up to 20%) is reported.

10acatalysis10acoordination10aHydroformylation10aPhosphine-phosphite ligand10aPhosphite ligand1 aKumar, Rohit1 aSen, Anirban1 aChikkali, Samir, H. uhttps://library.ncl.res.in/content/rh-catalyzed-asymmetric-hydroformylation-olefins-using-phosphorus-ligands