ChemInform Abstract: FLUOROMETHYL FORMATE. SYNTHESIS, MICROWAVE SPECTRUM, STRUCTURE, DIPOLE MOMENT, AND ANOMERIC EFFECT

Rotational Spectrum, Conformational Composition, and Quantum Chemical Calculations of Cyanomethyl Formate (HC(O)OCH2C≡N), a Compound of Potential Astrochemical Interest

“…The CCSD prediction that I and II are much lower (∼23 kJ/ mol) in energy than III is in accord with the propensity of formic acid esters to prefer sp conformations for the C2−O4− C5−O6 link of atom, as exemplified by HC(O)OCH 3 , 10 HC(O)OCH 2 CH 3 , 24,25 and HC(O)OCH 2 F. 26 Conformer III The Journal of Physical Chemistry A Article has a Boltzmann factor relative to I as low as about 8 × 10 −5 at room temperature, which means that III will have an extremely weak MW spectrum that would be impossible to detect with our spectrometer. This rotamer is therefore not considered further.…”

“…The existence of two conformers such as I and II with similar energies is typical for substituted formate esters and has already been found for HC(O)OCH 2 CH 3 24, 25 and HC(O)OCH 2 F. 26 The C2−O4−C5−C6 chain of atoms takes the expected 180°a ngle in I, and the unusual value of 80.3°in II ( Table 1). The corresponding C−O−C−C dihedral angle is 180°and 81.7°( r α 0 -structure) in the corresponding two conformers of HC(O)OCH 2 CH 3 , 25 a A-reduction, I r -representation.…”

“…corresponding C−O−C−C dihedral angle is 180°and 81.7°( r α 0 -structure) in the corresponding two conformers of HC(O)OCH 2 CH 3 , 25 whereas the C−O−C−F dihedral angle is 180°and 84(1)°in the two conformers of HC(O)OCH 2 F 26. …”