01721nas a2200241 4500008004100000245008700041210006900128260000800197300001600205490000800221520091800229100002501147700002001172700002501192700002301217700001901240700002301259700002201282700002301304700001901327700002001346856011301366 2016 eng d00aDynamic, reversible oxidative addition of highly polar bonds to a transition metal0 aDynamic reversible oxidative addition of highly polar bonds to a cDEC a16140-161470 v1383 aThe combination of Pt complexes and indium trihalides leads to compounds that form equilibria in solution between their In X oxidative addition (OA) products (Pt indyl complexes) and their metal-only Lewis pair (MOLP) isomers (LnPt -> InX3). The position of the equilibria can be altered reversibly by changing the solvent, while the equilibria can be reversibly and irreversibly driven toward the MOLP products by addition of further donor ligands. The results mark the first observation of an equilibrium between MOLP and OA isomers, as well as the most polar bond ever observed to undergo reversible oxidative addition to a metal complex. In addition, we present the first structural characterization of MOLP and oxidative addition isomers of the same compound. The relative energies of the MOLP and OA isomers were calculated by DFT methods, and the possibility of solvent-mediated isomerization is discussed.1 aBertermann, Ruediger1 aBoehnke, Julian1 aBraunschweig, Holger1 aDewhurst, Rian, D.1 aKupfer, Thomas1 aMuessig, Jonas, H.1 aPentecost, Leanne1 aRadacki, Krzysztof1 aSen, Sakya, S.1 aVargas, Alfredo uhttps://library.ncl.res.in/content/dynamic-reversible-oxidative-addition-highly-polar-bonds-transition-metal00974nas a2200193 4500008004100000022001400041245010700055210006900162260000900231300001600240490000700256520029500263100001700558700002400575700001800599700001700617700001900634856012700653 2021 eng d a1359-734500aDeoxygenative hydroboration of primary and secondary amides: a catalyst-free and solvent-free approach0 aDeoxygenative hydroboration of primary and secondary amides a ca cOCT  a10596-105990 v573 aIn contrast to the recent reports on catalytic hydroboration of amides to amines with pinacolborane (HBpin), a simple catalyst-free and solvent-free method for the hydroboration of a variety of amides has been realized. To get the mechanistic insights, DFT calculations have been performed.1 aKumar, Rohit1 aBisai, Milan, Kumar1 aJain, Shailja1 aVanka, Kumar1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/deoxygenative-hydroboration-primary-and-secondary-amides-catalyst-free-and-solvent-free01122nas a2200217 4500008004100000022001400041245007300055210006900128260000900197300001400206490000700220520043800227100001700665700002300682700002400705700001900729700001500748700001700763700001900780856010500799 2021 eng d a1359-734500aDiverse reactivity of carbenes and silylenes towards fluoropyridines0 aDiverse reactivity of carbenes and silylenes towards fluoropyrid cMAY  a4428-44310 v573 a

The reaction of IDipp with C5F5N led to functionalization of all three carbon atoms of the imidazole ring with HF2- as the counter-anion (1). Reactivity with 2,3,5,6-tetrafluoropyridine gives only C-F bond activation leaving C-H bonds intact (5b). The reaction of SIDipp with C5F5N in the presence of BF3 afforded the ring cleavage product (3). Analogous reactions with silylene led to oxidative addition at the Si(II) center.

1 aKundu, Gargi1 aAjithkumar, V., S.1 aBisai, Milan, Kumar1 aTothadi, Srinu1 aDas, Tamal1 aVanka, Kumar1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/diverse-reactivity-carbenes-and-silylenes-towards-fluoropyridines01891nas a2200193 4500008004100000022001400041245011100055210006900166260000900235300001400244490000700258520120400265100002401469700002601493700001501519700001701534700001901551856012701570 2021 eng d a0020-166900aDiverse reactivity of hypersilylsilylene with boranes and threecomponent reactions with aldehyde and HBpin0 aDiverse reactivity of hypersilylsilylene with boranes and threec cFEB  a1654-16630 v603 a

The recently reported hypersilylsilylene PhC-(NtBu)(2)SiSi(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 the rupture of the B-H bond of HBpin (7), where the hydride was bound to the carbon atom of the amidinate ligand and the Bpin unit was attached to the silicon center. Surprisingly, the reaction of 1 with HBcat results in PhC(NtBu)(2)Bcat (8). Subsequently, we have shown that HBcat forms the same product when it reacts with related silylene PhC(NtBu)(2)SiN(SiMe3)(3) (1'). With all of these reactions in hand, we ponder if silylene can activate two small molecules at one time. In this work, we delineate the three-component reactions of silylenes 1 and 1' with 4-fluorobenzaldehyde and HBpin, which afforded unusual coupling products, 9 and 10, respectively. Note that 9 and 10 were prepared from the cleavage of the B-H and C=O bonds by silylene in a single reaction and are the first structurally attested Si-C-O-B coupled products.

1 aBisai, Milan, Kumar1 aSwamy, V., S. V. S. N1 aRaj, Vipin1 aVanka, Kumar1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/diverse-reactivity-hypersilylsilylene-boranes-and-threecomponent-reactions-aldehyde-and02228nas a2200157 4500008004100000022001400041245008900055210006900144260000800213300001400221490000700235520167400242100001701916700001901933856011801952 2025 eng d a1477-922600aDevelopment of six-membered saturated cyclic diaminocarbenes in main-group chemistry0 aDevelopment of sixmembered saturated cyclic diaminocarbenes in m cJUN a9113-91240 v543 a

In recent years, there has been a remarkable surge in the utilization of saturated N-heterocyclic carbenes (NHCs) as ligands in main group chemistry. While the field has predominantly focused on five-membered NHCs and cyclic alkyl(amino) carbene (CAAC) ligands, the investigation of six-membered NHCs (6-NHCs) has only just begun. Despite possessing higher nucleophilicity than their five-membered counterparts, 6-NHCs have been less explored due to their lack of structural rigidity. This feature article aims to highlight recent developments in 6-NHCs in only main group chemistry. Exciting new studies have demonstrated the activation of B-H bonds in HBpin, ring expansion from a six-membered to a seven-membered ring under ambient conditions, and the stabilization of transient units ``H-B 00000000 00000000 00000000 00000000 11111111 00000000 11111111 00000000 00000000 00000000 O'' and ``(OH)BO'', among other intriguing phenomena. A major focus of this review is on synthetic approaches for 6-NHC-stabilized main-group compounds and their unusual properties, as revealed by spectroscopic and crystallographic data. While the chemistry of 6-NHCs is still in its nascent stage, the findings presented in this feature article underscore the need for its exploration and further investigation. Furthermore, this review provides valuable insights into effective synthetic methods for creating new 6-NHCmain group (B, Al, Si, P, Zn, etc.) complexes, along with mechanistic explanations for some of these reactions. These advances hold great promise for the future development of this exciting and rapidly evolving field of N-heterocyclic carbene chemistry.

1 aKundu, Gargi1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/development-six-membered-saturated-cyclic-diaminocarbenes-main-group-chemistry