Click Chemistry by Microcontact Printing

摘要

Microcontact printing (CP) is commonly used to pattern self-assembled monolayers (SAMs) as etch resists or chemical templates on gold and silicon oxide substrates.[1] However, CP can also be used for chemical synthesis on gold and silicon oxide in the nanoscale confinement between stamp and substrate. Amines can be printed onto reactive anhydride SAMs.[2] Peptides can be synthesized by printing N-protected amino acids onto an amine SAM.[3] It has been proposed that the confinement of the ink at the interface between the elastomeric stamp and the SAM, in combination with the preorganization of the reactants in the monolayer, facilitates the formation of covalent peptide bonds.[3] Recently, we demonstrated imine formation through the CP of amines on aldehyde SAMs[4] and applied this chemistry to directing the immobilization of cytophilic proteins.[5] Herein, we present a Huisgen 1,3-dipolar cycloaddition, as a representative example of the Sharpless click chemistry,[6] induced without any catalyst by CP of acetylenes onto azido-terminated SAMs on silicon oxide substrates.