Organic Lab Reactions 101

Organic Lab Reactions 101 - the same scheme with...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
96 THE CANNIZZARO REACTION these enzyme and catalytic reactions than between either of them and the true Cannizzaro reaction. MECHANISM OF THE REACTION A number of mechanisms have been suggested for the Cannizzaro reaction. 13 - 14 > 1B One mechanism, based upon a proposal by Lock, 16 who patterned his suggestion after those put forward by Grignard and Fluchaire 16 and by Fredenhagen and Bonhoeffer, 17 is the following. o- RCHO + OH" ^ RCH OH o- RCH + RCHO ;=± RCHOCHR \ I I OH OH O- OH RCHOCHR -> RCHJSOCR + 0H~ ?i RCH 2 0CR OH O- 0 0 - OH RCH 2 0CR -* RCH 2 0H + RCOs" o- This mechanism adequately coordinates the well-known variations of base-induced dismutations of aldehydes into a general picture and makes it unnecessary to suppose that different bases act in different ways. The formation of esters when an aldehyde is treated with an alkoxide follows
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: the same scheme, with OR"" in place of 0H~, and takes into account the ester interchanges which have been observed to occur. The transforma-tion of benzaldehyde into benzamide and benzyl alcohol by the action of sodamide 18 proceeds analogously, amide-ester interchange brought about by the amide ion being the last step. 13 Hammett, "Physical Organic Chemistry," p. 350, McGraw-Hill, New York, 1940. 14 Eistert, "Tautomerie und Mesomerie," p. 116, Enke, Stuttgart, 1938. 16 Eitel and Lock, Monatsh., 72, 392 (1939). 16 Grignard and Fluchaire, Ann. chim., [10] 9, 5 (1928). 17 Fredenhagen and Bonhoeffer, Z. physik. Chem., A181, 379 (1938). 18 Haller and Bauer, Ann. chim. phys. 16, 145 (1909)....
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online