Synthesis and Crystal Structure of Bis[O,O'-di(2-phenylethyl)dithiophosphato](α,α'-bipyridine)copper(Ⅱ)

A ternary adduct Cu[S2P（OCH2CH2Ph）2]2·bipy（bipy=α,α＇-bipyridine） was syn-thesized and characterized by elemental analysis,IR and single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P1 with a=10.2320（2）,b=11.5249（3）,c=18.0916（3）,α=98.95（1）,β =103.601（1）,γ=91.272（2）°,V=2044.49（7）3,Z=2,Dc=1.453 g/cm3,T=153（2） K,C42H44CuN2O4P2S4,Mr=894.51,λ（MoKα）=0.71073,μ=0.86 mm-1,S=0.999,（△/σ）max=0.002,the final R=0.0243 and wR=0.0704.A total of 9221 unique reflections were collected,of which 8573 with Ⅰ 〉2σ（Ⅰ） were observed.The Cu（Ⅱ） atom is five-coordinated in a rather distorted trigonal bipyramidal geometry（τ value=0.537）.The Cu-S distances range from 2.3491（4） to 2.4829（4） ,and the Cu-N distances are 1.9987（12） and 2.0584（11） ,respectively.An interesting feature of this adduct resides in its two-dimensional（2D） open framework constructing through hydrogen bonding and π-π interactions.

Direct Optical Resolution of Chiral Pesticides by High Performance Liquid Chromatography

Enantiomer separation is one of the most important prerequisites for the investigation of environmental enantioselective behavior for chiral pesticides.The enantiomeric separation of three chiral pesticides,indoxacarb,lambda-cyhalothrin,and simeconazole,were studied on cellulose tris-(3,5-dimethylphenyl-carbamate)-coated chiral stationary phase(CDMPC-CSP) using high-performance liquid chromatography under normal phase condition.The effects of chromatographic conditions,such as the mobile phase composition including the concentration and type of alcohol modifiers in hexane,flow rate and column temperature,on enantiomer separation were examined.The thermodynamical mechanism of enantioseparation and chiral recognition mechanism were discussed.Better separation were achieved using 20% n-propanol for indoxacarb,2% iso-butanol for lambda-cyhalothrin,and 20% iso-propanol for simeconazole as modifiers in hexane at 25℃ with the selectivity factor(a) of 1.69,1.82 and 1.70,respectively.The resolution factor(Rs) decreased as the flow rate increased from 0.4 to 1.1 ml·min-1.The retention factor(k') and selectivity factor for the enantiomers of analytes decreased as temperature increased.The lna-1/T plots for racemic chiral pesticides were linear in the range of 15-35℃ in hexane/iso-propanol and the chiral separation was controlled by enthalpy.Hydrogen bonding,π-π and dipole-dipole interactions between enantiomers and CDMPC-CSP play an important role in chiral identification,and the fitting of the asymmetric portion of solutes in a chiral cavity or channel of the CSP is also important.