Dichloromethane → Tributyltin fluoride

Participants

Reaction Conditions

Reaction Steps

1 is halogenated chromophore 2 is metalated conjugated system step a) Reaction of 1 and 2 by palladium mediated Stille coupling results in formation of compound 3; step b) The carboxylaldehyde moiety is introduced to compound 3 by Vilsmaier-Haak reaction; And step c) transformed by reaction of 4 with cyano-acetic acid to the targeted 5. Step a) Under inert atmosphere, to a mixture of chromophore 1, 1 mol % catalysator Pd(PPh3)4, 1 equivalent of CsF in toluene, 1.2 equivalent of tributylstannyl-thiophene were added. The reaction mixture was stirred at 120° C. for 12 h. After cooling to room temperature, dichloromethane was added. The white salt (Bu3SnF) formed during the reaction was filtered off and the solvent removed under reduced pressure. Purification of the crude product was performed by column chromatography on silica gel with (2/8) dichloromethane/ethylacetate to give the pure thiophene derived squarylium dye 3. Analytical Data for 3

Provenance & Evidence