Computational Prediction of ¹H and ¹³C Chemical Shifts: A Useful Tool for Natural Product, Mechanistic, and Synthetic Organic Chemistry

Computational Prediction of ¹H and ¹³C Chemical Shifts: A Useful Tool for Natural Product, Mechanistic, and Synthetic Organic Chemistr

Total Synthesis of Oxidized Welwitindolinones and (−)-<i>N</i>-Methylwelwitindolinone C Isonitrile

We report the total synthesis of (−)-<i>N</i>-methylwelwitindolinone C isonitrile, in addition to the total syntheses of the 3-hydroxylated welwitindolinones. Our routes to these elusive natural products feature the strategic use of a deuterium kinetic isotope effect to improve the efficiency of a late-stage nitrene insertion reaction. We also provide a computational prediction for the stereochemical configuration at C3 of the hydroxylated welwitindolinones, which was confirmed by experimental studies

Effect of Isotopically Sensitive Branching on Product Distribution for Pentalenene Synthase: Support for a Mechanism Predicted by Quantum Chemistry

Mechanistic proposals for the carbocation cascade reaction leading to the tricyclic sesquiterpene pentalenene are assessed in light of the results of isotopically sensitive branching experiments with the H309A mutant of pentalenene synthase. These experimental results support a mechanism for pentalenene formation involving a 7-protoilludyl cation whose intermediacy was first predicted using quantum-chemical calculations

Experimental and Theoretical Investigations of the Bromination of Phenols with β and γ Aliphatic Substituents, including Rings

Bromination reactions of substituted and ring fused phenols were studied by both experiment (<i>t</i>-BuNH-Br) and computation (density functional theory). The outcomes support each other, indicating a clear and predictable regioselective preference among 3,4-bis-alkylated and 3,4-ring-fused phenols