Procedure:  15 mL 1-neck flask, stirbar, septum, N₂ inlet, condenser

                  6 mL of a 1:1 mixture of concentrated H₂SO₄ in water was added to a flask containing 0.833 g of nitrile I.  The reaction mixture was stirred and heated to reflux.  After 2 h, the reaction mixture was poured into 50 mL of ice water and 9 mL of 10 M NaOH (aq.) was added.  The pH was then further raised to 3-4 with sat. aq. NaHCO₃ while maintaining the temperature at 0 C with ice.  A white precipitate formed which was collected by filtration and washed with ether to afford the product. 

 

mp >220 C

 

The product proved to be particularly insoluble and was characterized as its methyl ester: ¹H NMR (CDCl₃, 300 MHz) d 7.34 (dd, J = 8.8, 4.9 Hz, ArH, 2H), 7.00 (dd(apparent t), J = 8.5 Hz, ArH, 2H), 3.65 (s, CO₂CH₃, 3H), 2.77 (m, piperidine CH₂s, 2H), 2.55 (m, piperidine CH₂s, 2H), 2.26 (s, NCH₃, 3H), 2.11 (m, piperidine CH₂s, 2H), 1.93 (m, piperidine CH₂s, 2H). 

 

notes