Organic Reactions Volume 4 - Sciencemadness Dot Org

366 ORGANIC REACTIONS
well as on the usual preparative scale. 14 ' u No variation in the yield with
the quantity of reactants has been reported.
A few acid chlorides have been converted to aldehydes by vaporphase
catalytic reduction. Excellent yields of benzaldehyde and isovaleraldehyde
have been obtained 35 by passing the acid chlorides and
hydrogen at atmospheric pressure over palladinized asbestos at about
200°. Phenylacetyl chloride, however, gave phenylethyl alcohol and
ethylbenzene, and succinyl chloride gave butyrolactone. Aromatic and
higher aliphatic chlorides have been reduced 36 > 37 to aldehydes by operating
at reduced pressures with nickel, nickel chloride, and platinum as
catalysts. These methods appear to present no definite advantage.
EXPERIMENTAL CONDITIONS AND REAGENTS
Preparation of the Acid Chloride. The acid chloride may be prepared
by any one of the usual methods, 38 " 57 but it should be purified by distillation
or crystallization immediately before use. The thionyl chloride
method is to be preferred to those using phosphorus halides. Though
traces of thionyl chloride do not affect the Rosenmund reduction appreciably,
phosphorus compounds are more serious poisons, and even traces
may retard or prevent the reduction. 68,69
84 Barnes, Org. Syntheses, 21, 110 (1941).
8B Frdsohl and Danofif, /. prakt. Chem., [2] 144, 217 (1936).
36 Grignard and Mingasson, Compt. rend., 185, 1173 (1927).
87 Escourrou, Bull. soc. chim. France, (5), 6, 1173 (1939).
88 Clark and Boll, Trans. Roy. Soc. Can., [3] 27, 97 (1933).
89 Meyer, Monatsh., 22, 415 (1901).
40 Silberrad, J. Soc. Chem. Ind., 45, 36, 55 (1926).
41 McMastor and Ahmann, J. Am. Chem. Soc, 50, 145 (1928).
42 Spilth and Spitzer, Ber., 59, 1477 (1926).
43 Meyer and Graf, Ber., 61, 2202 (1928).
44 Fuson and Walker, Org. Syntheses, Coll Vol. 2, 169,
46 Helferich and Schaofer, Org. Syntheses, Coll. Vol. 1, 147, 2nd ed.
40 Martin and Fioser, Org. Syntheses, Coll. Vol. 2, 569.
47 Fieser and Peters, J. Am. Chem. Soc, 54, 4373 (1932).
48 Carre" and Liberrnann, Compt. rend., 199, 1422 (1934).
40 Kissling, Ger. pat., 701,953 [C. A., 86, 99 (1942)].
60 Kyrides, /. Am. Chem. Soc, 59, 206 (1937).
51 Kyrides, Org. Syntheses, 20, 51 (1940).
52 Ruggli and Maeder, HeIv. Chim. Acta, 26, 1476 (1943).
53 Carr6 and Liberrnann, Compt. rend., 201, 147 (1935).
54 Webb and Corwin, /. Am. Chem. Soc, 66, 1456 (1944).
55 Boon, /. Chem. Soc, 1945, 601.
56 Wood, Jackson, Baldwin, and Longenecker, J. Am. Chem. Soc, 66, 287 (1944).
57 Adams and Ulich, J. Am. Chem. Soc, 42, 599 (1920).
58 Zetzsche and Arnd, HeIv. Chim. Acta, 8, 591 (1925).
59 Zetzsche and Arnd, HeIv. Chim. Ada, 9, 173 (1926).