Nitrite (NO) and nitroso compounds (E-NO, E = RS, RO, and RN) in mammalian plasma and cells serve important roles in nitric oxide (NO) dependent as well as NO independent signaling. Employing an electron deficient β-diketiminato copper(II) nitrito complex [ClNN]Cu(κ-ON)·THF, thiols mediate reduction of nitrite to NO. In contrast to NO generation upon reaction of thiols at iron nitrite species, at copper this conversion proceeds through nucleophilic attack of thiol RSH on the bound nitrite in [Cu](κ-ON) that leads to S-nitrosation to give the S-nitrosothiol RSNO and copper(II) hydroxide [Cu]-OH. This nitrosation pathway is general and results in the nitrosation of the amine PhNH and alcohol BuOH to give PhNNO and BuONO, respectively. NO formation from thiols occurs from the reaction of RSNO and a copper(II) thiolate [Cu]-SR intermediate formed upon reaction of an additional equiv thiol with [Cu]-OH.

Undirected C(sp 3 ) À Hf unctionalization reactions often follow site-selectivity patterns that mirror the corresponding CÀHbond dissociation energies (BDEs). This often results in the functionalization of weaker tertiary CÀHb onds in the presence of stronger secondary and primary bonds.A n important, contemporary challenge is the development of catalyst systems capable of selectively functionalizing stronger primary and secondary CÀHbonds over tertiary and benzylic CÀHsites.Herein, we report aCucatalyst that exhibits ahigh degree of primary and secondary over tertiary CÀHb ond selectivity in the amidation of linear and cyclic hydrocarbons with aroyl azides ArC(O)N 3 .M echanistic and DFT studies indicate that C À Ha midation involves H-atom abstraction from R-H substrates by nitrene intermediates [Cu](k 2 -N,O-NC(O)Ar) to provide carbon-based radicals RC and copper-(II)amide intermediates [Cu II ]-NHC(O)Ar that subsequently capture radicals RC to form products R-NHC(O)Ar.T hese studies reveal important catalyst features required to achieve primary and secondary C À Ha midation selectivity in the absence of directing groups.

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The synthesis and characterization of a series of novel iron complexes has been accomplished using a monoanionic pincer bis­(carbene) ligand framework. Metalation first proceeded through an isolated Fe­(II) zwitterionic intermediate that was subsequently reduced in situ to Fe(0) to facilitate oxidative addition of the aryl C–H bond, generating the FeII–H complexes. Varying the L-type ligand on these complexes exhibited profound effects, as observed by IR and 1H NMR spectroscopy. Higher oxidation states of Fe could also be supported in this ligand framework, as evidenced by the isolation of two Fe­(III) complexes. Treating an FeII–H complex with CO2 generated an Fe–formate complex (κ2-OOCH) from insertion into the FeII–H bond. The independent synthesis of this molecule was accomplished by treating FeII–Cl with excess NaOOCH.

Undirected C(sp 3 ) À Hf unctionalization reactions often follow site-selectivity patterns that mirror the corresponding CÀHbond dissociation energies (BDEs). This often results in the functionalization of weaker tertiary CÀHb onds in the presence of stronger secondary and primary bonds.A n important, contemporary challenge is the development of catalyst systems capable of selectively functionalizing stronger primary and secondary CÀHbonds over tertiary and benzylic CÀHsites.Herein, we report aCucatalyst that exhibits ahigh degree of primary and secondary over tertiary CÀHb ond selectivity in the amidation of linear and cyclic hydrocarbons with aroyl azides ArC(O)N 3 .M echanistic and DFT studies indicate that C À Ha midation involves H-atom abstraction from R-H substrates by nitrene intermediates [Cu](k 2 -N,O-NC(O)Ar) to provide carbon-based radicals RC and copper-(II)amide intermediates [Cu II ]-NHC(O)Ar that subsequently capture radicals RC to form products R-NHC(O)Ar.T hese studies reveal important catalyst features required to achieve primary and secondary C À Ha midation selectivity in the absence of directing groups.