Microwave spectrum, dipole moment, and conformation of bicyclo[3.1.0]hexane

Abstract

The microwave spectrum of bicyclo[3.1.0]hexane has been studied in the range 26.5-40.0 GHz ( band) with a Hewlett-Packard Model 8400 Stark-modulated microwave spectrometer. The rotational constants (MHz) for the ground vibrational state have been determined to be A = 5542.

Theoretical Study of Structures and Ring-Puckering Potential Energy Functions of Bicylo[3.1.0]hexane and Related Molecules

“…Figure shows the calculated ring-puckering angles (Θ) of the five-membered rings and also the dihedral angles between the two rings (α). Table compares the calculated bond distances and angles within the rings and the dihedral angles Θ and α to the experimental values from microwave spectroscopy − and electron diffraction. , It is gratifying to see how well the calculations agree with the experimental data as this also demonstrates that the previous experimental data had been correctly analyzed. The agreement is poorest for the ring-puckering angle, but the fact that the ring-puckering vibration is of large amplitude means that the potential energy changes only slightly as the molecule puckers away from its energy minimum.…”

“… a Microwave data from ref . b Combined electron diffraction and microwave analysis, ref . c MP2/cc-pVTZ calculations. This work. d Electron diffraction data from ref . e Microwave data from ref . …”

Photocycloadditions of tetrachloro-1,4-benzoquinone (chloranil) onto cyclobutene and cyclopropene. Expected and unexpected products

“…This pattern is typical for the boat conformation of the bicyclo[3.1.0]hexane skeleton, 14 which has been known for the parent hydrocarbon for a long time. 15,16 The multiplicity of the signal of the CHCl group is revealing as well, as it is a triplet with a line distance of 9.2 Hz. Thus, this proton is coupled equally strongly with both protons of the neighbouring methylene group.…”

“…, 255 (10), 253 (15), 249 (15), 227 (11), 225 (14), 199 (12), 162 (11), 115 (14), 71 (79), 58 (100) and 45 (17).…”

Beiträge zur Strukturchemie phosphorhaltiger Ketten und Ringe

“…Im Gegensatz hierzu und zum Cyclohexan selbst bevorzugen die Bicyclo[3.1.0]hexane und analoge Systeme eine wannenartige Konformation, wie mikrowellen- (Cook et al, 1974;Mjöberg et al, 1976) und schwingungsspektroskopische Untersuchungen (Lord et al, 1973 ;Lewis et al, 1974) und die daraus hergeleiteten Abstandsverteilungen und Potentialfunktionen nahelegen, theoretische Rechnungen zu begründen versuchen (Mjöberg et al, 1978) Bicyclo[3.1.0]hexan selbst wird durch die Wanne eine gestaffelte Anordnung der Wasserstoff-Substituenten an den Atompaaren C t , C 2 bzw. 5).…”