Spectral investigations of some piperidin-4-one molecular addition compounds

In the present study, some 2- and 3-substituted piperidin-4-ones (A(1)-A(3)) were chosen as proton acceptor and maleic anhydride was chosen as proton donor. Piperidin-4-ones (A(1), A(2) & A(3)) were mixed with maleic anhydride in ether medium and the corresponding molecular adduct products (B-1, B-2 & B-3) thus obtained were collected and purified. The H-1 and C-13 NMR spectra were recorded for piperidine-4-one and their addition compounds. The H-1 and C-13 NMR chemical shifts of products (B-1, B-2 & B-3) are analyzed and compared with those of the corresponding piperidine-4-ones (A(1), A(2) & A(3)). In order to confirm the formation of molecular addition compounds the GC-Mass spectrum was recorded for all adducts B-1-B-3 and the fragmentations patterns were analyzed.