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In the title compound, Na+·C14H11O2?, the di­phenyl­acetate ions have a conformation where the two phenyl rings and the carboxyl­ate group are oriented like the blades of a propeller, each ion having a well defined helicity. The crystal structure of the title compound is achiral, although non‐centrosymmetric (space group ); thus, ions with both (+) and (?) helicities are present in the crystal. Each Na+ ion is coordinated by four carboxyl­ate O atoms at distances in the range 2.207 (2)–2.467 (3) Å to form cubes of Na and O atoms which are linked via the carboxyl­ate C atoms into a columnar structure along the rotoinversion axis.  相似文献   
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A phosphorus ylide bearing a 10-phenylsulfonylisoborneol unit reacted with ketenes, generated in situ from acid chlorides and triethylamine, to give allenic compounds. The reaction with methylketene led to asymmetric induction with the selective synthesis of an allene with axial chirality corresponding to an S configuration. The structure of the chiral allene 10-phenylsulfonylisobornyl penta-2,3-dienoate was determined by X-ray crystallography. Chirooptical studies of the chiral allene derivatives were done.  相似文献   
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The title compound, [Cu4Cl8(C4H9NO2)4], crystallizes in the centrosymmetric space group P21/c with a unit cell containing two tetra­nuclear copper(II) complexes sited on crystallographic inversion centres. The coordination geometry around the central Cu atoms is square pyramidal, with four O atoms in the basal plane and a Cl atom in the apical position. The lateral CuCl4 groups are flattened tetra­hedral. The bridging dimethyl­glycine mol­ecules are present in the dipolar zwitterionic form. The tetra­nuclear copper complexes exist as isolated entities since only intra­molecular hydrogen bonds are found.  相似文献   
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The title compound, C5H12NO2+·C2HO4·C5H11NO2 or HC2O4·(HBET·BET)+ [BET is tri­methyl­glycine (betaine); IUPAC name: 1-carboxy-N,N,N-tri­methyl­methanaminium hydro­xide inner salt], contains pairs of betaine mol­ecules bridged by an H atom, forming dimers linked by a strong hydrogen bond. The hydrogen oxalate anions have a rather unusual star conformation, with an internal torsion angle of 70.1 (4)°. The betaine–betainium dimers are anchored between two zigzag chains of hydrogen oxalate mol­ecules hydrogen bonded head-to-tail running parallel to the b axis. An extended network of C—H⃛O interactions links the anionic chains to the cationic dimers.  相似文献   
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