Gas phase analogues of solvolysis reactions

The Coordination Chemistry of the CF Unit in Fluorocarbons.

The physical properties and chemical reactivities of organic molecules can be dramatically affected by fluorination. Today’s diverse commercial applications of organo-fluorine materials clearly manifest the possible beneficial effects of fluorination, and the numerous ways in which industry has taken practical advantage of these effects are the subjects of the following chapters in this book. This chapter focuses on the characteristic substituent effects that underlie the physicochemical properties of organofluorine compounds, especially those important to the design of commercial products. Fortunately, advances in both experimental and theoretical physical organofluorine chemistry over the past two decades have made the “unusual” behavior of fluorinated compounds much more understandable and predictable. General principles that govern the characteristic effects of fluorination will be presented, but important exceptions also will be noted. Misleading generalizations like “fluorination increases lipophilicity” and myths about fluorine steric effects will be dispelled, for example.

Characteristics of C-F Systems

Acetic acid: Microwave spectra, internal rotation and substitution structure

The free jet millimeter wave spectra of four isotopomers of the 1:1 complex between difluoromethane and water have been observed and assigned. The water molecule lies in the FCF plane of difluoromethane, linked through an O−H···F hydrogen bond to one fluorine atom, and entgegen to the second one. The H bond parameters are r(F···H) = 2.20 A, ∠(F···H−O) ≅ 135°, and ∠(C−F···H) ≅ 93°, respectively. The oxygen is zusammen to the C atom, and the “free” water hydrogen is entgegen to the difluoromethane moiety. The value of 90° of the C−F···H angle is indicative of the preservation of the p character of the lone pairs of fluorine in the adduct.

The C−F···H−O Hydrogen Bond in the Gas Phase. Rotational Spectrum and ab Initio Calculations of Difluoromethane-Water

Internal hydrogen bond, torsional motion, and molecular properties of 2-methoxyethylamine by microwave spectroscopy Methyl barrier to internal rotation for 2-methoxyethanol

Methyl and skeletal torsion interaction in methyl thiolfluoroformate

Evidence of the weakness of the OH⋯F hydrogen bond from a conformational study of 3-fluoro-1-propanol by microwave spectroscopy

Equilibrium configuration of acetic acid

Methyl barrier to internal rotation and quadrupole coupling constants in S-methylchlorothioformate

Walther Caminati

Papers

Internal hydrogen bond, torsional motion, and molecular properties of 2-methoxyethylamine by microwave spectroscopy Methyl barrier to internal rotation for 2-methoxyethanol

Methyl and skeletal torsion interaction in methyl thiolfluoroformate

Evidence of the weakness of the OH⋯F hydrogen bond from a conformational study of 3-fluoro-1-propanol by microwave spectroscopy

Equilibrium configuration of acetic acid

Methyl barrier to internal rotation and quadrupole coupling constants in S-methylchlorothioformate