Example 10
Complex Mixture Em5-i:
A solution of 0.60 g of Em5-s complex mixture in 200 ml of 3-methoxypropionitril is irradiated with a blacklight blue lamp at room temperature for 7 h (Osram, L18W/73, λmax=370-380 nm). The solvent is removed under reduced pressure. The residue is carefully washed with methanol. This gives 0.10 g of Em5-i as a pale yellow powder (17%, again mixture of two cyclometalation isomers).
MS (Maldi):
m/e=1110 (M+H)+
Photoluminescence (in a film, 2% in PMMA):
λmax=456,487 nm, CIE: (0.20; 0.34)
The photoluminescence quantum yield of the isomerized Em5-i complex mixture has 1.50 times the quantum yield of the Em5-s complex mixture.