Organic electroluminescent materials and devices

The invention relates to organic electroluminescent materials and devices. Compounds comprising a first ligand LA are disclosed. In LA, ring B is a 5-membered or 6-membered ring; y is O, S, NRY or CRYRY '; z1 is O, S, NR or CRR '; x1 is C or N; each R, R ', RY, RY', RA and RB is hydrogen or a substituent; lA is coordinated with metal M through a dotted line; any two of R, R ', RY, RY', RA and RB may be joined to form a ring; and with the proviso that the compound does not comprise formula II: wherein Z'and Z ''are each C or N. Formulations, OLEDs, and consumer products containing the compounds are also disclosed. 本申请涉及有机电致发光材料和装置。公开了包含的第一配体LA的化合物。在LA中，环B是5元或6元环；Y是O、S、NRY或CRYRY'；Z1是O、S、NR或CRR'；X1是C或N；每个R、R'、RY、RY'、RA和RB是氢或取代基；LA通过虚线与金属M配位；R、R'、RY、RY'、RA和RB中的任何两个可接合形成环；并且其限制条件是，所述化合物不包含式II：其中Z'和Z"各自是C或N。还公开了含有所述化合物的调配物、OLED和消费型产品。