Anthracene-based organic dyes and preparation methods thereof

An organic dye having a structure of formula (II);

• wherein Ra is formula (Ra-1), formula (Ra-2), formula (Ra-3), (Ra-4), formula (Ra-5), formula (Ra-6), or formula (Ra-7):
• wherein Ra-3-3, Ra-3-4, Ra-6-3, and Ra-6-4 are independently selected from H or a C1-C36alkyl group;
• wherein Ra-1-1, Ra-1-2, Ra-2-1, Ra-2-2, Ra-3-1, Ra-3-2, Ra-4-1, Ra-4-2, Ra-5-1, Ra-5-2, Ra-6-1, and Ra-6-2 are independently selected from H, a C1-C36 alkyl group, or a C1-C36 alkoxy group;
• wherein Ra-2-3, Ra-2-4, Ra-2-5, Ra-2-6, Ra-5-3, Ra-5-4, Ra-5-5, and Ra-5-6 are independently selected from H, a C1-C36 alkyl group, a phenyl group substituted with a C1-C36 alkoxy group, or a phenyl group substituted with a C1-C36 alkyl group;
• wherein Ra-7-1 is selected from H, a C1-C36 alkyl group, or a C1-C36 alkoxy group;
• and
• wherein z is 0 or 1;
• wherein Rb is formula (Rb-1), formula (Rb-2), formula (Rb-3), or formula (Rb-4):
• wherein x and y are independently selected from 0 or 1, and both R4 and R5 are H;
• wherein A is a C6-C30 aryl group, a C4-C30 oxygen-containing heteroaryl group, a C4-C30 sulfur-containing heteroaryl group, a C4-C30 selenium-containing heteroaryl group, or a C4-C30 tellurium-containing heteroaryl group;
• wherein R2-1, R2-2, R2-3, and R2-4 are independently selected from H, a C1-C36 alkyl group, a phenyl group substituted with a C1-C36 alkyl group, or a phenyl group substituted with a C1-C36 alkoxy group.