Method for synthesis of iriduim (III) complexes with sterically demanding ligands
Phosphorescent materials and devices with improved device manufacturing, fabrication, stability, efficiency, and/or color.
1. A process for making an Ir(L a )(L b )(L c ) complex, comprising:
reacting an intermediate having the formula (L a )(L b )IrX with L c to produce an Ir(L a )(L b )(L c ) complex,
where L a , L b and L c are, independently, bidentate cyclometallated ligands having the formula:
where R 3 , R 4 , R 5 , R 6 , R′ 3 , R′ 4 , R′ 5 , and R′ 6 are independently selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, alkylaryl, CN, NO 2 , halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group;
where at least one of R 6 or R′ 3 is not hydrogen, and R 6 or R′ 3 is selected from the group consisting of alkyl, alkenyl, alkynyl, alkylaryl, CN, CO 2 R, C(O)R, NR 2 , NO 2 , OR, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, and a heterocyclic group;
X is
2. The process of claim 1 , wherein L a , L b , and L c are photoactive.
3. The process of claim 2 , wherein R′ 6 is hydrogen, and R 3 is selected from the group consisting of alkyl, alkenyl, alkynyl, alkylaryl, CN, NO 2 , halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, and a heterocyclic group.
4. The process of claim 3 , wherein the yield of Ir(L a )(L b )(L c ) is at least 50%.
5. The process of claim 3 , wherein the yield of Ir(L a )(L b )(L c ) is at least 30%.
6. The process of claim 2 , wherein R 3 is hydrogen, and R′ 6 is selected from the group consisting of alkyl, alkenyl, alkynyl, alkylaryl, CN, NO 2 , halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, and a heterocyclic group.
7. The process of claim 5 , wherein the yield of Ir(L a )(L b )(L c ) is at least 10%.
8. The process of claim 2 , wherein L a , L b , and L c are the same.
9. The process of claim 2 , wherein R 6 is methyl, and R 3 , R 4 , R 5 , R′ 3 , R′ 4 , R′ 5 and R′ 6 are hydrogen.
10. The process of claim 2 , wherein R′ 3 is methyl, R′ 5 is methyl, R 4 is methyl and R 3 , R 5 , R 6 , R′ 4 , and R′ 6 are hydrogen.
11. The process of claim 2 , wherein R′ 3 is methyl, R′ 5 is methyl, and R 3 , R 4 , R 5 , R 6 , R′ 4 , and R′ 6 are hydrogen.