106656-92-2Relevant articles and documents
Further Studies on the Stereochemistry of Sparteine, Its Isomers and Derivatives. XV. Synthesis, Structure and Spectroscopic Properties of the 2-Methyl-2-dehydrosparteine and 2-(p-Tolyl)-2-dehydrosparteine (Free Base) and Their Diprotonated Salts
Boczon, Wladyslaw
, p. 21 - 36 (2007/10/02)
A syntesis of 2-methyl-2-dehydrosparteine (IV) has been modified and, for the first time, 2-(p-tolyl)-2-dehydrosparteine (V) has been obtained.Disalts of these compounds have been obtained: diperchlorates IV and V and dihydrochloride V.The characteristics of the compounds are given including their structures and protonation sites obtained on the grounds of IR spectra.Both compounds IV and V, similarly as the previously obtained 2-phenyl-2-dehydrosparteine (II) are found to occur in the same configuration-conformation system: trans A/B chair/chair-trans C/D boat/chair.The conformation of IV and V remains unchanged in their disalts in which the immonium bonds =C(2)=N(1)+= are present.The differences observed in IR spectra within the range 1600 - 1800 cm-1 are mainly a consequence of different interactions of chloride and perchlorate anions with cation fragments of the disalts of IV and V.Similarly as in II, crystalline monosalts of IV and V could not be obtained.Quite recently X-ray analysis confirmed our suggestions as to their structure.On the grounds of pK'MCS measurements, the proton-acceptor properties of the compounds studied are discussed.
