Furan and Selenophene Derivatized Benzo [1,2-b:4,5-b'] Dithiophene-Thienothiophene Based Conjugated Polymers For High-Efficiency Organic Solar Cells

8) A monomer solution, comprising:

• a) At least one furan, thiophene or selenophene derivatized benzo[1,2-b:3,4-b′]dithiophene monomer dissolved in anhydrous tetrahydrofuran, from about 3 to about 5 mmol;
• b) N-butyllithium, from about 8.5 to about 9.5 mmol;
• and
• c) Trimethylstannane, from about 10 to about 12 mmol.

9) A polymer solution, comprising:

• a) At least one first reactant selected from the group consisting of 1-(4,6-dibromo-3-fluorothieno[3,4-b]thiophen-2-yl)-2-ethylhexan-1-one and 2-ethylhexyl 4,6-dibromo-3-fluorothieno[3,4-b]thiophene-2-carboxylate dissolved in from about 4:1 to about 6:1 toluene and dimethylformamide, from about 0.25 to about 0.35 mmol;
• b) At least one second reactant selected from the group consisting of bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl)bis(trimethylstannane) and (4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl)bis(trimethylstannane) dissolved in the toluene and dimethyformamide solvent, from about 0.25 to about 0.35 mmol;
• and
• c) palladium-tetrakis(triphenylphosphine) catalyst, from about 1.5 to about 2.5 mg/mL.