Ethanal is heated with excess methanal and $Ca (OH) X_{2}$ . Three successive crossed aldol additions occur at the alpha carbon, and the resulting trihydroxy aldehyde is then reduced by a crossed Cannizzaro reaction with methanal. The final organic product is

A3-hydroxy-2,2-bis(hydroxymethyl)propanal
Bpropane-1,2,3-triol
C2,2-bis(hydroxymethyl)propane-1,3-diol
D2-(hydroxymethyl)propane-1,3-diol

Answer: C

Ethanal has three alpha-hydrogens and each adds to a methanal, giving

(HOCH X_{2}) X_{3} C - CHO

. This aldehyde has no alpha-hydrogen, so with methanal it undergoes crossed Cannizzaro reaction; methanal is oxidised and the aldehyde is reduced. The product is

C (CH X_{2} OH) X_{4}

, pentaerythritol.

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Ethanal is heated with excess methanal and Ca(OH)X2​. Three successive crossed aldol additions occur at the alpha carbon, and the resulting trihydroxy aldehyde is then reduced by a crossed Cannizzaro reaction with methanal. The final organic product is

Answer: C

More questions on Aldol, Cannizzaro, Perkin, Claisen and related condensations

Ethanal is heated with excess methanal and $Ca (OH) X_{2}$ . Three successive crossed aldol additions occur at the alpha carbon, and the resulting trihydroxy aldehyde is then reduced by a crossed Cannizzaro reaction with methanal. The final organic product is