Prepd from 2,6-dichloro-3-ethyl-4-methylpyridine by reduction with HI and red phosphorus: Ruzicka, Fornasir, Helv. Chim. Acta 2, 338 (1919); from 3-acetyl-1,4-dimethyl-1,2,5,6-tetrahydropyridine: Prelog, Komzak, Ber. 74, 1705 (1941); from γ-methylnicotinic acid: Rabe, Jantzen, Ber. 54, 925 (1921); from β-ethylpyridine: Koenigs, Hoffmann, Ber. 58, 194 (1925); from crotonaldehyde and ammonia: Tschitschibabin, Oparina, Ber. 60, 1877 (1927).