question_answer

Complete each synthesis by filling the missing starting materials, reagents or products (X, Y and Z). (i) \[{{C}_{6}}{{H}_{5}}CHO+C{{H}_{3}}C{{H}_{2}}CHO\xrightarrow{NaOH}X\] (ii) \[C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}C{{H}_{2}}OH\xrightarrow{Y}\,C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}COOH\] (iii)\[C{{H}_{3}}{{(C{{H}_{2}})}_{9}}COO{{C}_{2}}{{H}_{5}}\xrightarrow{Z}\,C{{H}_{3}}{{(C{{H}_{2}})}_{9}}CHO\]

Answer:

                (i)                 \[\underset{\text{Benzaldehyde}}{\mathop{{{C}_{6}}{{H}_{5}}-\overset{\begin{smallmatrix}  O \\  || \end{smallmatrix}}{\mathop{C}}\,-H}}\,+\underset{\text{Propanal}}{\mathop{C{{H}_{3}}C{{H}_{2}}CHO}}\,\xrightarrow[\begin{smallmatrix}  \,\,\text{(Claisen}\,\text{Schmidt} \\  \,\,\,\,\,\text{condensation)} \end{smallmatrix}]{NaOH}\]\[\underset{\text{Aldol}}{\mathop{\left[ {{C}_{6}}{{H}_{5}}-\overset{\begin{smallmatrix}  \,\,\,\,\,OH \\  | \end{smallmatrix}}{\mathop{C}}\,H-\overset{\begin{smallmatrix}  C{{H}_{3}} \\  | \end{smallmatrix}}{\mathop{C}}\,H-CHO \right]}}\,\xrightarrow[-{{H}_{2}}O]{{}}\]                                                                                            \[\underset{\begin{smallmatrix}   \\  \text{2-Methyl-3-phenylprop-2-en-1-al}\,(X) \end{smallmatrix}}{\mathop{{{C}_{6}}{{H}_{5}}-\overset{3}{\mathop{C}}\,H=\overset{\begin{smallmatrix}  C{{H}_{3}} \\  | \end{smallmatrix}}{\mathop{2C\,}}\,-CHO}}\,\] (ii)\[\underset{\text{Butan-1-ol}}{\mathop{C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}OH}}\,\,\xrightarrow[(ii)\,{{H}^{+}},\,{{H}_{2}}O]{(i)\,Alk.\,KMn{{O}_{4}}}\,\underset{\text{Butanoic}\,\,\text{acid}}{\mathop{C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}COOH}}\,\] (iii) \[\underset{\text{Ethyl}\,\text{undecanoate}}{\mathop{C{{H}_{3}}{{(C{{H}_{2}})}_{9}}COO{{C}_{2}}{{H}_{5}}}}\,\xrightarrow[(ii)\,{{H}_{2}}O]{(i)\,DIBAL-H}\,\underset{\text{Undecanal}}{\mathop{C{{H}_{3}}{{(C{{H}_{2}})}_{9}}CHO}}\,\] Thus, Y = (i) Alk. \[KMn{{O}_{4}},\](ii)\[{{H}^{+}},\,{{H}_{2}}O\] and \[Z=(i)\]\[DiBAL-H,\](ii)\[{{H}_{2}}O\]