The effect of terminal substitution on the helical carbon structure of fluoro-alkane chains: a pure rotational study of (N = 4, 5,& 6)

Abstract

Continuing a series of studies to investigate the change in structure of hydrocarbons as the amount of fluorination is increased to varying degrees of substitution, we present a survey on the change in the helical nature of the fluorinated carbon backbone when a $^{-}$CH$_{2}$OH group is substituted for a terminal $^{-}$ CF$_{3}$ group. Spectra for 1H,1H-heptafluorobutan-1-ol, 1H,1H-nonafluoropentan-1-ol, and 1H,1H-undecafluorohexan-1-ol were collected separately using a chirped-pulse FTMW spectrometer in the range of 7-13 GHz. Only one conformation was observed for each molecule. Additional measurements of the 1H,1H-heptafluorobutan-1-ol were completed using a Balle-Flygare cavity instrument. Assignments of the singly-substituted $^{13}$C isotopologues of the 1H,1H-heptafluorobutan-1-ol were also measured. A comparison of both \textit{ab initio} and experimental structures will be presented.