Organic electroluminescent materials and devices

1 . An organic light emitting device (OLED) comprising:

an anode;

a cathode; and

an emissive region, disposed between the anode and the cathode;

wherein the emissive region comprises:

a first compound that is a sensitizer having a structure of

wherein:

M-C is a metal carbene bond;

M is selected from the group consisting of Cu, Ag, and Au;

X 1 is selected from the group consisting of CR, CRR′, NR, O, S, PR, SiRR′, BR, and GeRR′;

Y′ is N;

n is 1;

represents a single bond or a double bond;

R, R′, R A , R B , and R C is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, boryl, 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;

R D and R E are each substituted or unsubstituted aryl;

any two or more of R, R′, R A , R B , R C , R D , and R E can be joined or fused together to form a ring;

R A and R B are joined to form a ring;

R D and R E are joined to form a ring;

and

wherein the OLED further comprises an acceptor, wherein the acceptor has the structure:

wherein:

rings A, B and C are each independently a monocyclic or multicyclic ring system comprising one or more fused 5-membered or 6-membered carbocyclic or heterocyclic rings;

Z is B;

each Y is NR; and

each R is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, boryl, 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

with the proviso that when X 1 is CRR′, the acceptor emits light with a peak wavelength Amax of less or equal to 520 nm at room temperature.

2 . The OLED of claim 1 , wherein the first compound has a structure selected from the group consisting of:

wherein each M, X 1 , Y 1 , R A , R B , R C , R D , R E in a given formula can be same or different, and

wherein in Formula II and Formula IV, each n is 1.

3 . The OLED of claim 1 , wherein at least one of the following is true:

(a) R D and R E are each a 6-membered aromatic ring, and can be substituted;

(b) R D and R E are joined together with Y′ to form a 5-membered ring;

(c) R A and R B are joined together to form a 5-membered or 6-membered ring; and

(d) R C is a 6-membered aromatic ring, and can be substituted.

4 . The OLED of claim 1 , wherein X 1 is NR or CR.

5 . The OLED of claim 1 , wherein the acceptor emits light with a peak wavelength Amax of less or equal to 520 nm at room temperature.

6 . The OLED of claim 1 , wherein the fraction

in Formula I comprises a structure selected from the group consisting of:

wherein:

the dashed line or lines in each structure represents a direct bond to an M;

each X is independently C or N;

each R G , R H , R I , R J , R K , R L , R P , R O , R R , R Y , and R Z is independently a hydrogen or a substituent selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, boryl, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, and combinations thereof; and

each R F —R M , R P , R O , R S , R T , R Y , and R Z independently represents zero, mono to the maximum allowable substitution.

7 . The OLED of claim 1 , wherein the fraction

in Formula I is selected from the group consisting of:

wherein

each X is independently selected from the group consisting of C and N but each X of a ring directly bonded to the N having the dashed bond is C;

each Y is independently selected from the group consisting of CRR′, SiRR′, NR, BR, O, S, Se, and PR;

R and R′each independently represents zero, mono to the maximum allowable substitution; and

each R and R′ is independently a hydrogen or a substituent selected from the group consisting of deuterium, fluorine, alkyl, cycloalkyl, heteroalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, aryl, heteroaryl, nitrile, isonitrile, sulfanyl, and combinations thereof.

8 . The OLED of claim 1 , wherein the emissive region comprises the acceptor.

9 . The OLED of claim 1 , wherein the emissive region comprises a first organic layer and a second organic layer, wherein the first organic layer comprises the first compound and the second organic layer comprises the acceptor.

10 . The OLED of claim 9 , wherein the first compound of Formula I is doped into the emissive region at a concentration ranging between 1 wt % and 25 wt %.

11 . The OLED of claim 10 , wherein the acceptor is doped into the emissive region at a concentration ranging between 0.1% and 5%.

12 . The OLED of claim 10 , wherein the emissive region further comprises a host.

13 . The OLED of claim 1 , wherein the acceptor is selected from the group consisting of:

14 . A consumer product comprising the OLED of claim 10 , wherein the consumer product is selected from the group consisting of a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior illumination and/or signaling, a heads-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a cell phone, tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display that is less than 2 inches diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, a light therapy device, and a sign.

15 . The OLED of claim 1 , wherein M is Cu.

16 . The OLED of claim 1 , wherein the first compound of Formula I is selected from the group consisting of:

17 . An organic light emitting device (OLED) comprising:

an anode;

a cathode; and

an emissive region, disposed between the anode and the cathode;

wherein the emissive region comprises:

a first compound that is a sensitizer having a structure of

wherein:

M-C is a metal carbene bond;

M is selected from the group consisting of Cu, Ag, and Au;

X 1 is selected from the group consisting of CR, CRR′, NR, O, S, PR, SIRR′, BR, and GeRR′;

Y 1 is N;

n is 1;

represents a single bond or a double bond;

R, R′, R A , R B , and R C is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, boryl, 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;

R D and R E are each substituted or unsubstituted aryl;

any two or more of R, R′, R A , R B , R C , R D , and R E can be joined or fused together to form a ring;

R A and R B are joined to form a ring;

R D and R E are joined to form a ring;

and

wherein the OLED further comprises an acceptor, wherein the acceptor comprises

18 . The compound of claim 17 , wherein the first compound is selected from the group consisting of:

19 . The compound of claim 18 , wherein the first compound is