Monomer-on-Monomer (MoM) Mitsunobu Reactions and ROMP-Derived Oligomeric Phosphates for the Application in Parallel Synthesis.

Abstract

The development of facilitated, chromatog.-free Mitsunobu protocols and new ROMP-derived oligomeric phosphate reagents for application in purifn.-free parallel synthesis are reported. A Monomer-on-Monomer (MoM) Mitsunobu protocol utilizing norbornenyl-tagged benzylethyl azodicarboxylate (Nb-BEAD) and Nb-tagged triphenylphosphine (Nb-TPP) is presented whereby purifn./ sequestration of Nb-tagged reagents is rapidly achieved using ring-opening metathesis (ROM) polymn. Addnl. efforts utilizing surface-initiated polymn. from Nb-tagged silica (Nb-Si) and Nb-tagged Cobalt-graphite (Nb-Co/C) magnetic nanoparticles is also discussed. An array of oligomeric benzyl phosphates (OBP) and their corresponding oligomeric triazole phosphate (OTP) derivs. were successfully synthesized for the efficient benzylation and triazolation of nucleophilic species. These oligomeric reagents are readily synthesized from com. available materials and are conveniently polymd. and purified in a one-pot process, affording pure white, free-flowing solids on multi-gram scale and in excellent yield. Utilization in benzylation and triazolation reactions with a variety of nucleophiles is also reported. [on SciFinder(R)]