Synthesis of a Bolaamphiphilic Alkenyl Phosphonic Acid by Ru-catalyzed Olefin Cross Metathesis Reaction

Abstract

We report the synthesis of bolaamphiphilic alkenyl phosphonic acid (BPC 12) through the olefin cross-metathesis reaction of vinylphosphonic acid with 1,11-dodecadiene in the presence of a Ru-carbene catalyst. BPC 12 possesses two trans-P-C=C moieties and is thus readily soluble in D 2 O up to 3.4 g L-1 , as confirmed by 1 H nuclear magnetic resonance (NMR) measurements. Surface tension measurements revealed that BPC 12 reduced the surface tension of water from 72.0 to 47.0 mN m-1. The occupied area per molecule (A) of BPC 12 (216 Å 2) was ten times larger than that of dodecenyl phosphonic acid PC 12 (23 Å 2). Moreover, dynamic light scattering measurement of an aqueous BPC 12 solution (5 mM) revealed the formation of large aggregates with an average estimated diameter of 81.8±27.0 nm.