Thor Gramstad

Studies of hydrogen bonding—part VII1: Hydrogen-bond association of phenol and pentachlorophenol with carbonyl compounds and ethers

Abstract The thermodynamic data for the 1:1 association of phenol with eight esters, three acid fluorides, sixteen ketones, fourteen aldehydes and fifteen ethers in carbon tetrachloride solution have been determined. It has been found that the frequency shifts, Δv oh , of the O-H band of phenol which accompanies the formation of the hydrogen bond with various types of proton acceptors NNdisubstituted amides, esters, ketones, aldehydes, ethers and organophosphorus compounds) are proportional to the corresponding ethalpies of association. This relationship is not applicable to other proton donors studied. The entropy of association (−ΔS) for the various systems is, in relation to Δv oh , in order of increasing values as follows: organophosphorus compounds-phenol

Studies of hydrogen bonding—VIII. Hydrogen-bond association between phenol and sulphoxides and nitroso compounds

Abstract The K ass , Δ H , Δ F , Δ S and v 1 2 values have been determined for the intermolecular hydrogen bond association of phenol to ten sulphoxides and three nitroso compounds. The effect of conjugation on the stretching frequency and on the hydrogen bonding ability of Pue5fbO, Sue5fbO or Cue5fbO groups is discussed and also the effect of sulphur in the groups R · S-Pue5fbO and R · S-Cue5fbO.

Studies of hydrogen bonding—XV. The influence of a SP bond in phosphoryl compounds on the PO stretching frequency and their hydrogen bonding ability

It has been found that the hydrogen bonding ability of phenol with phosphoryl compounds containing a Sue5f8P bond is, in relation to ΔvOH, significantly lower than that of other phosphoryl compounds. n nCorrelation of phosphoryl frequencies and hydrogen bonding abilities has shown that the sulphur atom in phosphorothiolates participates in resonance interaction through expansion of its valence shell.

Studies of hydrogen bonding—XVI the complexing of pentafluorophenol with triphenylphosphine oxide

Abstract It has been found that pentafluorophenol (PFP) forms hydrogen-bonded complexes with triphenylphosphine oxide (TPPO) of the type 1:1, 2:1 and 1:2. The K ass , Δ F , Δ H and Δ S values for the various complexes have been determined. The infra-red spectra in the Oue5f8H stretching vibration region for mixtures of various proton acceptors with PFP in carbon tetrachloride have been compared with the corresponding spectra using respectively phenol, pentabromophenol or pentachlorophenol as proton donor.

Studies ot hydrogen bonding—part IX1: The effect of solvent interaction on hydrogen bonding

Abstract A wide variety of mixed, solvents has been used to study the effect of solvent interaction on hydrogen bonding. The results are discussed in terms of specific interaction between the solvents and solutes. Due to specific solvation effect on the proton donor and acceptor, no general explanation of solvent interaction on the hydrogen bonded complex can be given.

Studies of hydrogen bonding—XIV Hydrogen bonding of indole to phosphoryl compounds

Abstract The K ass , ΔF, ΔH, ΔS and ν 1 2 values have been determined for the hydrogen bond association between indole and fifteen organophosphorus compounds (OPC). The relation between hydrogen bonding ability and Δν XH for various proton donors with OPC is discussed.

Studies of hydrogen bonding—XX. Hydrogen bonding ability of phosphoryl compounds containing N-P and S-P bonds

Abstract Replacement of one or two RS groups in (RS) 3 PO or ArS in (ArS) 3 PO with Et 2 N groups causing a great change in hydrogen bonding ability (or Δ v OH) and in the dipole moment, whereas the Pue5fbO streching frequency remains almost unaltered.

Studies of hydrogen bonding—XXI. A comparison between hydrogen bonding ability and infrared intensity of the proton accepting group

Abstract It has been found that there exists a reasonably good linear relationship between hydrogen bonding ability and infrared intensity of the proton accepting group (Pue5fbO, Oue5fbO).

Studies of hydrogen bonding—XIX. Hydrogen bonding ability of carbethoxymethylenetriphenylphosphorane

Abstract It has been found that carbethoxymethylenetriphenylphosphorane due to charge delocalization, is a very strong proton acceptor.