NOVELTY - Substituted 9H-fluorene compounds (I) are new.    USE - (I) are useful for organic electroluminescent devices such as an organic LED, an organic solar cell, an organo photoreceptor and an organic thin film transistor, which are useful in an electronic device (all claimed) such as cellular phone, personal digital assistant, electronic dictionary, portable media player, remote controller, navigation system, game console, TV and computers.    ADVANTAGE - (I) have excellent driving characteristic, rapid response speed and high color reproduction range, and improves the luminous efficiency, electric current density, brightness, driving voltage, thermal resistance, chromatic purity and lifetime of the device.    DETAILED DESCRIPTION - Substituted 9H-fluorene compounds of formula (I) are new.    R1-R5 = (a) H, D, halo, amino, nitrile, nitro, 1-60C alkyl, 1-60C alkoxy, 1-60C alkylamine, 6-60C arylamine, 1-60C alkyl thiophene, 6-60C aryl thiophene, 2-60C alkenyl, 2-60C alkynyl, 3-60C cycloalkyl, 6-60C aryl, 6-60C aryl substituted with deuterium, 8-60C alkenyl aryl, optionally substituted silane, optionally substituted boron, optionally substituted germanium, optionally substituted 2-20C heterocyclic or optionally substituted 6-60C aryl, (b) H, D, halo, CN, NO2, 1-60C alkyl, 1-60C alkyl, 1-60C alkoxy, 1-60C alkylamine, 6-60C arylamine, 7-60C alkylaryl, 8-20C alkenyl aryl, 1-60C alkyl thiophene, 2-60C alkenyl, 2-60C alkynyl, 3-60C cycloalkyl, 6-60C aryl, 6-60C aryl substituted with deuterium, optionally substituted silane, optionally substituted boron, optionally substituted germanium, acetylene or 2-60C heterocyclic optionally substituted with heteroatoms including O, N, S or Si, (c) H, D, halo, amino, nitrile, nitro, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 3-30C cycloalkyl, 6-60C aryl, deuterium-substituted 6-20C aryl, 2-20C heterocyclic or optionally substituted 1-30C alkoxy, (d) H, D, halo, amino, nitrile, nitro, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 3-30C cycloalkyl, 6-60C aryl, deuterium-substituted 6-20C aryl, 2-20C heterocyclic or optionally substituted 6-30C aryloxy, (e) halo, amino, nitrile, nitro, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 3-30C cycloalkyl, 6-60C aryl, 2-60C heteroaryl ring optionally substituted with 6-60C arylamine, or (f) 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl, 2-20C aryl substituted with deuterium, 8-20C alkylaryl, 8-20C arylalkenyl, 3-20C heterocyclic, nitrile or acetylene optionally substituted with 1-50C alkyl;    L = single bond, nitro, nitrile, halo, alkyl, alkoxy or amino (all optionally substituted with 6-60C aryl), or nitro, nitrile, halo, alkyl, alkoxy or amino (all optionally substituted with 2-60C heteroaryl); and    a = 0-2.    INDEPENDENT CLAIMS are included for:    (1) an organic electroluminescent device comprising an organic layer including (I); and    (2) an electronic device comprising the organic electroluminescent device and a control unit for driving the display device.