Pendant-bridging-chelating-cleavage: A series of bonding modes in ruthenium(II)-BINAPO complexes

Reaction of 1,1'-bis(diphenylphosphino)binaphthol (BINAPO, 1) with [RuCl2(η6-arene)]2 in methanol leads to dinuclear BINAPO-bridged Ru compounds [{RuCl2(η6-p-cymene)}2-(μ-BINAPO)], 2a, in near quantitative yield. In dichloromethane or acetonitrile, 1 preferably affords mononuclear species in which one of the phosphine centers remains uncoordinated. These complexes can be further stabilized by reaction with BH3 to afford, for example, [RuCl2(η6-p-cymene)(η1-BINAPO-BH3)], 4a. Upon heating a mixture of 1 and [RuCl2(η6-p-cymene)](2) in DMF, P-O bond cleavage occurs to afford [RuCl(η2-PPh2-BINOL)(η6-p-cymene)], 5a, bearing an anionic PO-chelating ligand. Ligand 1 acts as an intact chelate when reacted with [Ru2(μ-Cl)3(η6-p-cymene)2][PF6] to yield [RuCl(η6-p-cymene)(η2-BINAPO)][PF6], 7. Reaction of 1 with [RuCp(CH3CN)3] [PF6] in acetonitrile or chloroform affords [{RuCp(CH3CN)2}2(μ-BINAPO)][PF6]2, 8, and [RuCp(CH3CN)(η2 -BINAPO)][PF6], 9, respectively. The solid-state structures of 1, 2a, 4a, and 7 are reported, that of 2a representing a rare structural example of a molecule with a bridging binaphthyl-type ligand

Substantial improvements not seen in health behaviors following corner store conversions in two Latino food swamps

Abstract Background The effectiveness of food retail interventions is largely undetermined, yet substantial investments have been made to improve access to healthy foods in food deserts and swamps via grocery and corner store interventions. This study evaluated the effects of corner store conversions in East Los Angeles and Boyle Heights, California on perceived accessibility of healthy foods, perceptions of corner stores, store patronage, food purchasing, and eating behaviors. Methods Household data (n = 1686) were collected at baseline and 12- to 24-months post-intervention among residents surrounding eight stores, three of which implemented a multi-faceted intervention and five of which were comparisons. Bivariate analyses and logistic and linear regressions were employed to assess differences in time, treatment, and the interaction between time and treatment to determine the effectiveness of this intervention. Results Improvements were found in perceived healthy food accessibility and perceptions of corner stores. No changes were found, however, in store patronage, purchasing, or consumption of fruits and vegetables. Conclusions Results suggest limited effectiveness of food retail interventions on improving health behaviors. Future research should focus on other strategies to reduce community-level obesity