Unsymmetrical dialkyl sulfides for self-assembled monolayer formation on gold: Lack of preferential cleavage of allyl or benzyl substituents

Five unsymmetrical sulfides and one unsymmetrical disulfide were synthesize d for self-assembled monolayer (SAM) formation on gold electrodes. Each com pound contained a dinitrobenzyl ester group at the end of a primary alkyl c hain as one sulfide arm, with an allyl, methyl, or cyanobenzyl group for th e other arm. Cyclic voltammetry (CV) of the resulting SAMs showed no eviden ce for differential cleavage of allyl or cyanobenzyl sulfide groups relativ e to methyl, contrary to expectations if sulfide cleavage accompanied the s elf-assembly process.