Knowledge Bank

Infrared spectra of gaseous and solid cyclohexylphosphine and Raman spectra of the condensed phases of this compound have been recorded. Data for the most stable conformer are consistent with the microwave results which indicate the existence of a gaucheequatorial chair form. Additional conformations whose very weak lines in the room-temperature Raman spectrum are absent in the solid state have been observed and are at least 900 cal/mole less stable. The possible identities of these conformers will be discussed. Infrared and Raman spectra have likewise been recorded for 2-cyanoethylphosphine. There are two bonds about which internal rotation can give rise to conformers, and at least two, separated by approximately 300 cal/mole, have been observed. The number of depolarized lines in the Raman spectrum tentatively suggests that one of these is the $Cs$ conformer (Tt). The identities of the conformers will be discussed.