02097nas a2200169 4500008004100000245010400041210006900145260000800214300001400222490000600236520146300242100002501705700003001730700002001760700002101780856012601801 2017 eng d00aIron-catalyzed dehydrogenation reactions and their applications in sustainable energy and catalysis0 aIroncatalyzed dehydrogenation reactions and their applications i cAUG a3177-31950 v73 aInspired by nature, chemists have designed new catalysts in the pursuit of selective bond activation and chemical transformations. Emergent biological systems often use earth-abundant first-row transition elements as catalytically active sites to facilitate specific and highly selective chemical processes. The design of a new catalytic system based on abundant and inexpensive catalysts, particularly the iron-based catalysts, for fundamentally significant synthetic transformations under environmentally benign conditions is an important paradigm in chemical synthesis. In recent times, iron-based catalytic systems have shown unprecedented reactivity in the acceptorless dehydrogenation reactions of feedstock chemicals, with the liberation of molecular hydrogen as the by-product, and have enabled greener chemical synthetic methods and alternative energy storage systems. Indeed, it has been demonstrated that the proper design of iron catalysts by judiciously choosing ligands, can aid in the development of new sustainable energy storage systems and catalysis. This tutorial review focuses on the recent development of iron-based dehydrogenation reactions of fundamentally important feedstock, as a route to sustainable chemical synthesis and energy storage applications. The emerging area of the iron-based dehydrogenation strategy provides an opportunity to make industrially applicable, cost-effective and environmentally benign catalytic systems.1 aBalaraman, Ekambaram1 aNandakumar, Avanashiappan1 aJaiswal, Garima1 aSahoo, Manoj, K. uhttps://library.ncl.res.in/content/iron-catalyzed-dehydrogenation-reactions-and-their-applications-sustainable-energy-and01063nas a2200169 4500008004100000245007600041210006900117260000800186300001600194490000700210520048200217100002100699700002000720700002000740700002500760856010800785 2017 eng d00aOrgano-photoredox catalyzed oxidative dehydrogenation of N-heterocycles0 aOrganophotoredox catalyzed oxidative dehydrogenation of Nheteroc cOCT a14167-141720 v233 aWe report here for the first time the catalytic oxidative dehydrogenation of N-heterocycles by a visible-light organo-photoredox catalyst with low catalyst loading (0.1-1mol%). The reaction proceeds efficiently under base- and additive-free conditions with ambient air at room temperature. The utility of this benign approach is demonstrated by the synthesis of various pharmaceutically relevant N-heteroarenes such as quinoline, quinoxaline, quinazoline, acridine, and indole.1 aSahoo, Manoj, K.1 aJaiswal, Garima1 aRana, Jagannath1 aBalaraman, Ekambaram uhttps://library.ncl.res.in/content/organo-photoredox-catalyzed-oxidative-dehydrogenation-n-heterocycles01207nas a2200169 4500008004100000245015300041210006900194260000800263300001400271490000600285520052300291100002100814700002000835700002600855700002500881856013100906 2017 eng d00aRoom-temperature direct arylation of anilides under external oxidant-free conditions using CO2-Derived Dimethyl Carbonate (DMC) as a 'green' solvent0 aRoomtemperature direct arylation of anilides under external oxid cAUG a7565-75690 v23 a

Here, an efficient catalytic protocol for direct C-H bond arylation of anilides under base- and external oxidant-free conditions is reported. This reaction proceeds readily at room temperature using CO2-derived dimethyl carbonate (DMC) as a green solvent under visible-light dual catalysis. Later, application of our strategy for the gram-scale synthesis of Boscalid has been successfully shown. An unprecedented unsymmetrical bis-arylation of anilides is also demonstrated under mild, redox-neutral conditions.

1 aSahoo, Manoj, K.1 aRana, Jagannath1 aSubaramanian, Murugan1 aBalaraman, Ekambaram uhttps://library.ncl.res.in/content/room-temperature-direct-arylation-anilides-under-external-oxidant-free-conditions-using-co201321nas a2200181 4500008004100000022001400041245008800055210006900143260000900212300001400221490000700235520069700242100002100939700002000960700002200980700002501002856011201027 2017 eng d a1463-926200aUnified strategy for silver-, base-, and oxidant-free direct arylation of C-H bonds0 aUnified strategy for silver base and oxidantfree direct arylatio cMAY  a2111-21170 v193 a

Here, we report a dual catalytic approach for room temperature direct arylation of C-H bonds with aryldiazonium salts as a simple aryl group donor, also working as an internal oxidant via C-N-2 bond cleavage. This unified strategy has been achieved by the synergistic combination of visible-light metal-free photoredox and palladium catalysis under silver-, base-and/or additive-free conditions. The broad substrate scope, functional group tolerance, excellent regioselectivity and redox-neutral conditions of this process make it attractive for the effective synthesis of a wide range of important N-heterocyclic commodities such as dibenzo [b,d]azepine, carbazole and phenanthridine.

1 aSahoo, Manoj, K.1 aMidya, Siba, P.1 aLandge, Vinod, G.1 aBalaraman, Ekambaram uhttps://library.ncl.res.in/content/unified-strategy-silver-base-and-oxidant-free-direct-arylation-c-h-bonds00985nas a2200193 4500008004100000022001400041245015100055210006900206260000800275300001000283490000700293520025200300100002000552700002200572700002100594700002000615700002500635856013100660 2018 eng d a1359-734500aCobalt-catalyzed acceptorless dehydrogenative coupling of aminoalcohols with alcohols: direct access to pyrrole, pyridine and pyrazine derivatives0 aCobaltcatalyzed acceptorless dehydrogenative coupling of aminoal cJAN a90-930 v543 a

Here, the first example is reported of a new, molecularly defined SNS-cobalt(II) catalyst for the acceptorless dehydrogenative coupling (ADC) of unprotected amino alcohols with secondary alcohols leading to pyrrole and pyridine derivatives.

1 aMidya, Siba, P.1 aLandge, Vinod, G.1 aSahoo, Manoj, K.1 aRana, Jagannath1 aBalaraman, Ekambaram uhttps://library.ncl.res.in/content/cobalt-catalyzed-acceptorless-dehydrogenative-coupling-aminoalcohols-alcohols-direct-access01928nas a2200241 4500008004100000022001400041245009800055210006900153260000800222300001400230490000600244520110600250653003301356653001601389653001901405653001301424653002501437100002101462700003101483700002001514700002501534856012701559 2018 eng d a2155-543500aPhotocatalysis enabling acceptorless dehydrogenation of diaryl hydrazines at room temperature0 aPhotocatalysis enabling acceptorless dehydrogenation of diaryl h cAUG a7727-77330 v83 a

Aromatic azo compounds are privileged structural motifs, and they exhibit a myriad of pharmaceutical as well as industrial applications. Here, we report a catalytic acceptorless dehydrogenation of diarylhydrazine derivatives to access a wide variety of aryl-azo compounds with the removal of molecular hydrogen as the sole byproduct. This distinctive reactivity has been achieved under dual catalytic conditions by merging the visible-light active [Ru(bpy)(3)](2+) as the photoredox catalyst and Co(dmgH)(2)(py)Cl as the proton-reduction catalyst. The reaction proceeds smoothly under very mild and benign conditions and operates at ambient temperature. This dual catalytic approach is highly compatible with many different functional groups and has a broad substrate scope. We have also demonstrated the reversible hydrogen storage and release phenomenon on hydrazobenzene/azobenzene couple to show the utility of these compounds as hydrogen storage materials. Further diversification of azobenzene was shown by a transition metal-catalyzed azo-group-directed ortho-C-H bond functionalization.

10aacceptorless dehydrogenation10aAzo benzene10adual catalysis10aHydrogen10aphotoredox catalysis1 aSahoo, Manoj, K.1 aSaravanakumar, Krishnasamy1 aJaiswal, Garima1 aBalaraman, Ekambaram uhttps://library.ncl.res.in/content/photocatalysis-enabling-acceptorless-dehydrogenation-diaryl-hydrazines-room-temperature01362nas a2200169 4500008004100000245010900041210006900150260000800219300001400227490000700241520072800248100002000976700002600996700002101022700002501043856012401068 2019 eng d00aReusable cobalt catalyst for reversible acceptorless dehydrogenation and hydrogenation of N-Heterocycles0 aReusable cobalt catalyst for reversible acceptorless dehydrogena cMAY a2449-24570 v113 a

The development of robust catalytic systems based on basemetals for reversible acceptorless dehydrogenation (ADH) and hydrogenation of feedstock chemicals is very important in the context of ` hydrogen storage'. Herein, we report a highly efficient reusable cobalt-based heterogeneous catalyst for reversible dehydrogenation and hydrogenation of N-heterocycles. Both the ADH and the hydrogenation processes operate under mild, benign conditions.

1 aJaiswal, Garima1 aSubaramanian, Murugan1 aSahoo, Manoj, K.1 aBalaraman, Ekambaram uhttps://library.ncl.res.in/content/reusable-cobalt-catalyst-reversible-acceptorless-dehydrogenation-and-hydrogenation-n01316nas a2200157 4500008004100000022001400041245011600055210006900171260000900240300001400249490000700263520071100270100002100981700002501002856013101027 2019 eng d a1463-926200aRoom temperature catalytic dehydrogenation of cyclic amines with the liberation of H-2 using water as a solvent0 aRoom temperature catalytic dehydrogenation of cyclic amines with cAPR  a2119-21280 v213 a

Catalytic dehydrogenation of cyclic amines, in particular partially saturated N-heterocycles to N-heterocyclic arenes, with the removal of molecular hydrogen as the sole byproduct in water is reported. This dehydrogenation reaction proceeds smoothly under very mild and benign conditions and operates at room temperature. This distinctive reactivity has been achieved under dual catalytic conditions by merging the visible-light active [Ru(bpy)(3)](2+) as the photoredox catalyst and a newly synthesized cobalt complex as the proton-reduction catalyst. A detailed mechanistic study (control experiments, electrochemical studies, UV-visible experiments) is presented for the present dual catalysis.

1 aSahoo, Manoj, K.1 aBalaraman, Ekambaram uhttps://library.ncl.res.in/content/room-temperature-catalytic-dehydrogenation-cyclic-amines-liberation-h-2-using-water-solvent01493nas a2200205 4500008004100000022001400041245011700055210006900172260000900241300001400250490000800264520075900272100002101031700002401052700002101076700002201097700002501119700002001144856012301164 2019 eng d a0002-786300aTriazine functionalized porous covalent organic framework for photo-organocatalytic E-Z isomerization of olefins0 aTriazine functionalized porous covalent organic framework for ph cAPR  a6152-61560 v1413 a

Visible light-mediated photocatalytic organic transformation has drawn significant attention as an alternative process for replacing thermal reactions. Although precious metal/organic dyes based homogeneous photocatalysts have been developed, their toxic and nonreusable nature makes them inappropriate for large-scale production. Therefore, we have synthesized a triazine and a keto functionalized nonmetal based covalent organic framework (TpTt) for heterogeneous photo catalysis. As the catalyst shows significant absorption of visible light, it has been applied for the photocatalytic uphill conversion of trans-stilbene to cis-stilbene in the presence of blue light-emitting diodes with broad substrate scope via an energy transfer process.

1 aBhadra, Mohitosh1 aKandambeth, Sharath1 aSahoo, Manoj, K.1 aAddicoat, Matthew1 aBalaraman, Ekambaram1 aBanerjee, Rahul uhttps://library.ncl.res.in/content/triazine-functionalized-porous-covalent-organic-framework-photo-organocatalytic-e-z01170nas a2200181 4500008004100000022001400041245007300055210006900128260000800197490000700205520056700212100002100779700002300800700001900823700001900842700002500861856010200886 2021 eng d a1477-052000aConvenient semihydrogenation of azoarenes to hydrazoarenes using H-20 aConvenient semihydrogenation of azoarenes to hydrazoarenes using cJUN0 v193 a

The high atom-economical and eco-benign nature of hydrogenation reactions make them much more superior to conventional reduction and transfer hydrogenation. Herein, a convenient and highly selective hydrogenation reaction of azoarenes using molecular hydrogen to access diverse hydrazoarenes is reported. The present catalytic method is general and operationally simple, and it operates under exceedingly mild conditions (room temperature and 1 atm of hydrogen pressure). The reusability of catalysts used in this method is also successfully demonstrated.

1 aSahoo, Manoj, K.1 aSivakumar, Ganesan1 aJadhav, Sanjay1 aShaikh, Samrin1 aBalaraman, Ekambaram uhttps://library.ncl.res.in/content/convenient-semihydrogenation-azoarenes-hydrazoarenes-using-h-2