Question

Which of the following reactions will not result in the formation of carbon-carbon bonds?

• A. Reimer-Tiemann reaction
• B. Cannizaro reaction
• C. Wurtz reaction
• D. Friedel-Crafts- acylation

Answer 1

Answer: (B)

(a) Reimer-Tiemann reaction, (Here, a new C - C bond is formed.) Riemer-Tiemann reaction is an electrophilic substitution reaction. Cannizaro reaction (disproportionation reaction) In this reaction, 1-molecule of $HCHO$ convert in methanol and another molecule convert in salt. $2HCHO\stackrel{Conc.NaOH}{\to }C{H}_{3}OH+HCOONa$
(No new C-C bond is formed in this reaction.)
(c) Wurtz reaction, $R-X+2Na+R^{\prime }X+dryNa\stackrel{Ether}{\to }R-R$ Here, R and R'must be equal otherwise mixture of alkanes will form
(One new C-C bond is formed).
(d) Friedel-Craft's acylation, (New C-C bond is formed)
Thus, among the given reactions, only Cannizaro reaction does not involve the formation of a new C-C bond.