The Interpretation of the Vibrational Spectra of the C6 Hydrocarbons 22-Dimethyl Butane, 22-Dimethyl−3-Butene, and 22-Dimethyl−3-Butyne

Abstract

Assignments have been made for the observed infra‐red and Raman frequencies of the molecules 22‐dimethyl butane, 22‐dimethyl−3‐butene, and 22‐dimethyl−3‐butyne. By using the previously assigned characteristic frequency regions associated with the ethyl, vinyl, and C≡CH groups, it has been shown that the tertiary butyl group in all these molecules has frequencies near 1250, 1210(2), 1025(2), 880, and 700 cm⁻¹, in the range 1350–600 cm⁻¹. The assignment of these frequencies to skeletal C–C stretching and to methyl wagging modes is discussed.