Mechanistic Insights on N-Heterocyclic Carbene-Catalyzed Annulations: The Role of Base-Assisted Proton Transfers

• Published in: Journal of organic chemistry Vol. 76; no. 14; pp. 5606 - 5613
• Main Authors: Verma, Pragya, Patni, Priya A, Sunoj, Raghavan B
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.07.2011
• Subjects: Alicyclic compounds; Alicyclic compounds, terpenoids, prostaglandins, steroids; Catalysis; Chemistry; Cyclization; Cyclopentanes - chemical synthesis; Cyclopentanes - chemistry; Exact sciences and technology; Heterocyclic compounds; Heterocyclic Compounds - chemistry; Heterocyclic compounds with o, s, se, te hetero atom and condensed derivatives; Heterocyclic compounds with several n hetero atoms in the same ring, in separated rings or in fused rings; Kinetics and mechanisms; Methane - analogs & derivatives; Methane - chemistry; Molecular Conformation; Organic chemistry; Preparations and properties; Protons; Quantum Theory; Reactivity and mechanisms; Stereoisomerism; 1,8-Diazabicyclo[5.4.0]undec-7-ene; Catalytic reaction; Nitrogen heterocycle; Furan derivatives; Proton transfer; Theoretical study; Zwitterion; Experimental study; Oxygen heterocycle; Tetrahydrofurane; Energy barrier; Annelation; Solvation; Enolization; Thermodynamic parameter; Transition state; Reaction mechanism; Dichloromethane; Density functional method; Potential energy surfaces; Inclusion compound; Enone

The density functional theory investigation on the mechanism of NHC-catalyzed cycloannulation reaction of the homoenolate derived from butenal with pentenone is studied. The M06-2X/6-31+G** and B3LYP/6-31+G** levels of theory, including the effect of continuum solvation in dichloromethane and tetrah...