01819nas 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-rhodium01926nas 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