The performance of six newly synthesized benzo[h]quinoline-derived acetonitrilo pentamethylcyclopentadienyl iridium(III) tetrakis(3,5-bis-trifluoromethylphenyl)borate salts bearing different substituents À X (À OMe, À H, À Cl, À Br, À NO 2 and À (NO 2 ) 2 ) on the heterochelating ligand were evaluated in the dehydro-O-silylation of benzyl alcohol and the monohydrosilylation of 4-methoxybenzonitrile by Et 3 SiH, two reactions involving the electrophilic activation of the SiÀ H bond. The benchmark shows a direct dependence of the catalytic efficiency with the electronic effect of À X, which is confirmed by theoretical assessment of the intrinsic silylicities Π of hydridoiridium(III)-silylium adducts and by the theoretical evaluation of the propensity of hydridospecies to transfer the hydrido ligand to the activated substrate. The revisited analysis of the IrÀ SiÀ H interactions shows that the most cohesive bond in hydridoiridium(III)-silylium adducts is the IrÀ H one, while the IrÀ Si is a weak donor-acceptor dative bond. The Si…H interaction in all the cases is noncovalent in nature and dominated by electrostatics confirming the heterolytic cleavage of the hydrosilane's SiÀ H bond in this key catalytically relevant species.
Graphene oxide (GO) was chemically modified with para-aminobenzoic acid (PABA) to immobilize copper(ii) ions on its surface and used as a nanocatalyst for the oxidative C (sp2)–H bond amination reaction.
3-Phenyl-2-(1-H-pyrrol-1-yl) propanoic acid has been used as a ketene source in synthesizing of monocyclic-2-azetidinones. Hindrance in ketene and imines successfully controlled the diastereoselectivity of the reaction. For example, in some cases only one isomer was achieved. By using Mukaiyama reagent, the leaving group in acid was activated and the by-products were separated by simple aqueous work-up. DFT calculation indicated that the benzyl-N-pyrrolylketene has nonconjugated structure and the pyrrolyl ring is perpendicular to the ketene plane in both the twisted and planar structures.
Hetero‐Diels–Alder reactions of [60]fullerene with α,β‐unsaturated thio‐oxindoles (3a, 3b, 3c), prepared from thio‐oxindole 1 and heteroaromatic aldehydes (2a, 2b, 2c), to generate tetrahydrothiopyrano[2,3‐b]indole [60]fullerene cycloadducts (5a, 5b, 5c) under thermal or microwave irradiation were described. The yields were improved, and the reaction time was decreased by conducting the reaction under microwave irradiation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.