Marckwald cleavage

Under similar conditions, 2-furyl vinylcarbonyl systems (ketones, esters, acids) also produce keto esters. For example, 3-(2-furyl)acrylic acid 38, which is easily accessible from 2-furaldehyde by a decar-boxylating Knoevenagel reaction with malonic acid, yields the 3-oxoheptanedicarboxylic ester 39 (Marckwald cleavage) [9] ... 

Furylalcohols, for example, 2-furylmethanol (123), are ring-opened by HCl in alcohols to give esters of 4-oxopenanoic acid, for example, 124 (Marckwald cleavage [38]). Likewise, 2-furyl vinylcarbonyl systems (acids, esters, ketones) are cleaved by HCl/ROH, for example, 2-furyl acrylic acid (126) to the y-ketodiester 127. 

Madelung synthesis (indole) 137 Marckwald cleavage, of furans 79 Marckwald synthesis (imidazole) 224 Meth-Cohn synthesis (quinoline) 402 Meyer s oxazoline method 183 Morin reaction 456 Mukaiyama reaction 380 Mukaiyama reagents 53, 380... 

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