Question

Complete each synthesis by giving missing starting material, reagent, or products:

Hint:

Aldehydes react with hydroxylamine (\(\ce{HO-NH2}\)) in the presence of an acid to form oximes, which are useful intermediates in organic synthesis.

Answer 1

(a) The reaction involves the formation of hydroxylamine (NH₂OH) from an aldehyde (O) and hydroxylamine (HO-NH₂) in the presence of an acid catalyst (H⁺):

\( O + HO-NH_2 \xrightarrow{H^+} NH_2OH \)

(b) The reaction involves ozonolysis of ethene (CH₂=CH₂) followed by reductive workup to form formaldehyde (HCHO). Heating (\( \Delta \)) does not change the product further:

\( CH_2=CH_2 \xrightarrow{(i) O_3 (ii) Zn-H_2O} 2HCHO \xrightarrow{\Delta} \text{No further change} \)

(c) The reaction involves the conversion of an alcohol (OH) to an alkyl chloride (Cl) using thionyl chloride (SOCl₂) under heating (\( \Delta \)):

\( OH \xrightarrow{SOCl_2} Cl \)

(d) The reaction involves the conversion of an aldehyde (CHO) to a carboxylic acid (COOH) using sodium cyanide (NaCN) and hydrochloric acid (HCl):

\( CHO \xrightarrow{NaCN/HCl} COOH \)

(e) The reaction involves the methylation of chlorobenzene (Cl₂C₆H₅) to form a methylated chlorobenzene derivative (Cl₂C₆H₄CH₃):

\( Cl_2C_6H_5 \xrightarrow{CH_3} Cl_2C_6H_4CH_3 \)