Tungsten pentacarbonyl complexes of 1,3-benzoxaphospholes

2-R-1,3-Benzoxaphospholes (R-BOPs) are examples of fluorescent conjugated materials possessing low coordinate phosphorus centers. A series of 2-(p-XC6H4)-BOPs (X = H, Cl, Br, Me, OMe) react with [W(CO)(5)(NCMe)] to produce the crystalline complexes [W(CO)(5)(2-Ar-BOP)] (2a-e). All complexes were characterized by NMR spectroscopy and by single crystal X-ray diffraction. The crystal structures all displayed extensive pi-stacking of the BOP ligands and gear locking of the CO groups. Addition of the protecting [W(CO)(5)] group to the BOPs was discovered to significantly diminish fluorescence of the BOP moiety. (C) 2017 Elsevier B.V. All rights reserved.