Heterocyclic compound and organic light-emitting device comprising same

A heterocyclic compound represented by the following Chemical Formula

• wherein, in Chemical Formula 1,
• X is O or S,
• L is a direct bond;
• a substituted or unsubstituted C6 to C60 arylene group;
• or a substituted or unsubstituted C2 to C60 heteroarylene group,
• Z and R1 are each independently a substituted or unsubstituted C1 to C60 alkyl group;
• a substituted or unsubstituted C2 to C60 alkenyl group;
• a substituted or unsubstituted C2 to C60 alkynyl group;
• a substituted or unsubstituted C3 to C60 cycloalkyl group;
• a substituted or unsubstituted C2 to C60 heterocycloalkyl group;
• a substituted or unsubstituted C6 to C60 aryl group;
• a substituted or unsubstituted C2 to C60 heteroaryl group;
• a substituted or unsubstituted C1 to C20 alkylamine group;
• a substituted or unsubstituted C6 to C60 arylamine group;
• a substituted or unsubstituted C2 to C60 heteroarylamine group;
• or a substituted or unsubstituted phosphine oxide group,
• R2 to R5 are each independently hydrogen;
• deuterium;
• a halogen group;
• a cyano group;
• a substituted or unsubstituted C1 to C60 alkyl group;
• a substituted or unsubstituted C3 to C60 cycloalkyl group;
• a substituted or unsubstituted C6 to C60 aryl group;
• or a substituted or unsubstituted C2 to C60 heteroaryl group,
• a is an integer of 1 to 4,
• b is an integer of 1 to 3,
• m and n are each an integer of 1 to 5, and
• when a, b, m and n are each 2 or greater, substituents in the parentheses are the same as or different from each other.