Fluorene derivative and organic light emitting device comprising same

A fluorene derivative of one of Chemical Formulae 1-4 to 1-6:

• wherein in Chemical Formulae 1-4 to 1-6:
• Ar2 and Ar4 are hydrogen;
• b and d are an integer of 5;
• L1 is a direct bond, a substituted or unsubstituted arylene group, or a substituted or unsubstituted heteroarylene group, and L3 is a phenylene group, a biphenylylene group, a naphthylene group, a phenanthrene group, or a divalent fluorene group that is unsubstituted or substituted with an alkyl group having 1 to 10 carbon atoms;
• or
• L1 is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, and L3 is a direct bond, a phenylene group, a biphenylylene group, a naphthylene group, a phenanthrene group, or a divalent fluorene group that is unsubstituted or substituted with an alkyl group having 1 to 10 carbon atoms;
• X1 to X3 are the same as or different from each other, and each independently is N or CR1;
• two or more of X1 to X3 are N;
• R1 is hydrogen;
• R2 is hydrogen;
• Y1 and Y2 are the same as or different from each other, and each independently is deuterium, a substituted or unsubstituted alkyl group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group;
• and
• n is an integer of 4.