Crystal and molecular structure of 8-acetamido-2,4,4,8-tetramethyl-3-azaniumbicyclo[3.3.1]non-2-ene perchlorate

X-ray single crystal analysis sheds further light on the structure of this new iminium salt. ATABNEP crystallizes in the monoclinic system, space group P21 and shows a very short value for the C—N distance in the iminium group, thus suggesting that the contribution of the carbonium ion form in this particular case is much lower than usual, a fact that can be considered a rationale for the reluctance of ATABNEP to undergo hydrolysis.