AZAPROPELLANES AS PHASE-TRANSFER CATALYSTS-II A CMR AND PMR STUDY OF THE THREE-DIMENSIONAL STRUCTURE OF 1-AZONIAPROPELLANES CONTAINING 5- AND 6-MEMBERED RINGS

Article abstract of DOI:10.1016/0040-4020(82)80005-7

An improved synthesis of 1-azoniatricyclo<4.4.3.0^1,6>tridecane (2) and the preparation of the remaining member of the series, 1-azoniatricyclo<4.3.3.0^1,6>dodecane salts (3) have been achieved.Using a combination of ¹H (at 400 MHz) and ¹³C NMR spectra has allowed the assignment of the signals in the well-resolved ¹H spectra.The results indicate that 1 exists in the all-chair form which undergoes racemisation by ring inversion with a rate constant of 0.7 sec^-1 and further that the counterion in these salts is restricted to associating with only one face of the tetrahedral N atom.