Laboratory Methods of Organic Chemistry - Sciencemadness Dot Org

a-AMINOPYKIDINB 365
rH2
I 2 I -+ I ' I -+ I " |" +NC.C6HS.
CH2 CH2 CH2 CH2 CICH2CICH2
N.CO.C6H5
N.C(C1)2.C6HS
CN
(6) a-AMINOPYRIDINE !
Sodamide (10 g.) is ground under xylene in a mortar and added
to 16 g. (0-2 mole) of pyridine which has been dried over powdered
potassium hydroxide or barium oxide, distilled, and mixed with
30 c.c. of sodium-dried xylene. The mixture is then heated under
reflux in an oil bath at 14O°-150° for seven hours. Moisture must
be completely excluded. After cooling, 20 c.c. of cooled sodium carbonate
solution are gradually and cautiously added, the mixture is
shaken up, and the layers of liquid are then separated with a funnel.
The aqueous layer is extracted several times with benzene; the
extracts are combined and dried for a short time over solid potassium
hydroxide ; the solvents are removed by distillation. For purification
the high-boiling aminopyridine is distilled hi a vacuum (sausage
flask); the first portion of the distillate consists chiefly of xylene.
The base boils at 93°/ll mm. and 96°/13 mm. Yield 6-7 g. A
further small amount can be obtained from the first and last portions
of the distillate by fractionation. a-Aminopyridine crystallises easily
and can be recrystallised from ligroin. Melting point 57°.
1 Tschitschibabin, Chem. Zentr., 1915, I, 1065 ; Wibaut, Bee. trav. chim., 1923,
42, 240.