Method for preparing deuterated compound

A method for preparing a deuterated compound, the method comprising:

• preparing a compound of Chemical Formula 2 by reacting a compound of Chemical Formula 1;
• a deuterium source;
• and a metal catalyst, and
• forming a compound of Chemical Formula 3 reacting the compound of Chemical Formula 2,
• wherein in Chemical Formulae 1 to 3,
• R1 is hydrogen;
• a cyano group;
• a nitro group;
• a halogen group;
• a hydroxyl group;
• a substituted or unsubstituted alkyl group;
• a substituted or unsubstituted cycloalkyl group;
• a substituted or unsubstituted aryl group;
• or a substituted or unsubstituted heteroaryl group,
• R2 is hydrogen or deuterium,
• R3 is hydrogen;
• deuterium;
• a substituted or unsubstituted alkyl group;
• a substituted or unsubstituted cycloalkyl group;
• a substituted or unsubstituted aryl group;
• or a substituted or unsubstituted heteroaryl group,
• Ar1 and Ar2 are the same as or different from each other, and each independently a substituted or unsubstituted aryl group;
• or a substituted or unsubstituted heteroaryl group,
• L1 is a direct bond;
• a substituted or unsubstituted arylene group;
• or a substituted or unsubstituted heteroarylene group,
• D is deuterium,
• r1 is an integer of 0 to 8, r1′ is an integer of 0 to 4, r1″ is an integer of 0 to 3, and when r1, r1′ and r1″ are 2 or greater, R1s are the same as or different from each other,
• r3 is an integer of 0 to 8, and when r3 is 2 or greater, R3s are the same as or different from each other, and
• n1 is an integer of 1 to 5, and n2 is an integer of 1 to 4.