Universal Display Corporation
HOST MATERIALS FOR ELECTROLUMINESCENT DEVICES

Abstract:

A compound of Formula I: ##STR00001## wherein ring A is a 5-membered or 6-membered aromatic ring; wherein R.sup.A, R.sup.B, and R.sup.C each independently represent mono to the maximum allowable substitution, or no substitution; wherein Y.sup.1 is absent or present, and when present is selected from the group consisting of a direct bond, O, S, Se, CRR', NR, SiRR', and BR; wherein each X.sup.1-X.sup.3 is N or CR; wherein at least one of X.sup.1-X.sup.3 is N; wherein each A.sup.1-A.sup.5 is independently C or N; wherein the maximum number of N atoms that can connect to each other within each ring is two; wherein each R.sup.1, R.sup.2, R.sup.3, and R.sup.4 is independently selected from the group consisting of alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, aryl, heteroaryl, and combinations thereof; wherein each R, R', R.sup.A, R.sup.B, and R.sup.C is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof; and wherein any two substituents may be joined or fused together to form a ring.