The present manuscript investigates the solution coordinative chain transfer polymerization (CCTP) of isoprene initiated by the ternary Ziegler‐Natta catalyst system composed by neodymium versatate (NdV3), diisobutylaluminum (DIBAH), and dimethyldichlorosilane. A kinetic mechanism is proposed and the kinetic parameters are estimated to allow the appropriate description of dynamic trajectories of average molecular weights and isoprene conversions obtained in solution CCTP polymerizations for the first time. A data reconciliation strategy is applied to evaluate the amount of DIBAH used as a chain transfer agent, as this very active compound can be consumed by undesired side reactions. Additionally, the impacts of key operation variables on the control of the average molecular weights and monomer conversion are evaluated to elucidate the living nature of the polymerization. As observed experimentally, the temperature effect on the course of the polymerization is not so pronounced as the effect of NdV3, isoprene, and DIBAH initial concentrations. The kinetic mechanism is described better and kinetic constants are estimated more precisely when the dynamic trajectories of average molecular weights are fitted during the whole batch. In this case, the proposed model is able to predict well the experimental trajectories of average molecular weights of the produced polymer and monomer conversion.

The use of copper for C-H bond functionalization, compared to other metals, is relatively unexplored. Herein, we report a synthetic protocol for the regioselective hydroxylation of sp 2 and sp 3 C-H bonds using a directing group, stoichiometric amounts of Cu and H 2 O 2. A wide array of aromatic ketones and aldehydes are oxidized in the carbonyl γ-position with remarkable yields. We also expanded this methodology to hydroxylate the β-position of alkylic ketones. Spectroscopic characterization, kinetics, and density functional theory calculations point toward the involvement of a mononuclear LCu II (OOH) species, which oxidizes the aromatic sp 2 C-H bonds via a concerted heterolytic O-O bond cleavage with concomitant electrophilic attack on the arene system.

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In this article, we describe simple one‐pot syntheses of 2H‐1,3‐benzoxazines from ketones utilizing an imino‐pyridine directing group (R1R2‐C=N−CH2‐Pyr), which promotes a Cu‐directed sp2 hydroxylation using H2O2 as oxidant and followed by an oxidative intramolecular C−O bond formation upon addition of NEt3. This synthetic protocol is utilized in the gram scale synthesis of the 2H‐1,3‐benzoxazine derived from benzophenone. Mechanistic studies reveal that the cyclization occurs via deprotonation of the benzylic position of the directing group to produce a 2‐azallyl anion intermediate, which is oxidized to the corresponding 2‐azaallyl radical before the C−O bond formation event. Understanding of the cyclization mechanism also allowed us to develop reaction conditions that utilize catalytic amounts of Cu.