Palladium catalyzed reactions executed on solid-phase peptide synthesis supports for the production of self-assembling peptides embedded with complex organic electronic subunits
Methods to synthesize self-assembling peptides embedded with complex organic electronic subunits are provided.
1. A method for preparing one or more peptide-[(Ar 1 —Ar 2 —Ar 1 )]-peptide structures, the method comprising:
a) providing one or more peptides immobilized on a solid support, wherein the one or more peptides have a deprotected or free amine group;
b) contacting the one or more immobilized peptides with a portion of a π-conjugated subunit comprising a first arene (Ar 1 ) and differentially substituted with a halide and a carboxylic acid group to promote N-acylation of the amine termini of the one or more peptides;
c) contacting the one or more immobilized peptides of step (b) with a second arene (Ar 2 ) disubstituted with mutually reactive functionality for transmetallation in the presence of a palladium catalyst to promote site-site cross coupling dimerization between the disubstituted second arene and the two N-acylated amine termini of the one or more peptides formed in step (b); and
d) cleaving the product formed in step (c) to form one or more peptide-[(Ar 1 —Ar 2 —Ar 1 )]-peptide structures.
2. The method of claim 1 , wherein the first arene and the second arene can be the same or different and are each independently selected from the group consisting of thiophenyl, bithiophenyl, phenyl, and 1,4-diethynylphenyl.
3. The method of claim 1 , wherein the halide is selected from the group consisting of bromine and iodine.
4. The method of claim 1 , wherein the palladium catalyst is Pd(PPh 3 ) 4 .
5. The method of claim 1 , wherein the one or more peptide-[(Ar 1 —Ar 2 —Ar 1 )]-peptide structures are water soluble.
6. The method of claim 1 , wherein the one or more peptide-[(Ar 1 —Ar 2 —Ar 1 )]-peptide structures are selected from the group consisting of:
7. The method of claim 1 , comprising forming one or more peptide-[(Ar 1 —Ar 2 —Ar 1 )]-peptide structures comprising up to six π-conjugated units.