Novel ring opening of aminoheterocycles: Facile syntheses of ω-alkylaminopentadienenitriles

Easy Access to Medium Rings by Entropy/Strain Reduction. Part 3. Competition Between Dihydroazepine and Enamine Formation in Reaction of Tetrahalosubstituted Dibromides with Primary Amines.

“…This is further supported by the presence of an N-H signal at 3120 cm -1 in the ir spectrum although we found no corresponding signal in the 1 H nmr spectrum. In the latter the allylic methylene signals are replaced by a pair of mutually coupled doublets and a singlet in the alkene region while the benzylic signal is significantly shifted downfield to approximately 5.1 ppm consistent with literature examples of similar N-benzyl substituted secondary enamines [10]. Unfortunately, because of their substitution pattern, the stereochemistry of compounds 5 remains undetermined.…”

Ring lithiation of pyridones

“…This was purified by passage through a short column of silica gel in chloroform-methanol (2 : 1) to give the pure 2-deuteriopyridone (14b) (0.35 g, 91%) as a colourless crystalline solid, m.p. 91-5-H), 6.37 ( 1 H, s, 3-H), and 3.62 (3 H, s, NMe); m/z 110 (Mf', loo), 82 (23), 55 (8), and 42 (13).…”

“…6 k 7 . 2 0 ( 5 H, m, ArH), and 3.45 (3 H, s, NMe); mjz 215 ( M + ' , loo), 170 (23), 110 (22), and 77 (22).…”