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Two couples of enantiomedcally pure chiral cyano-bridged heterobimetallic chain coordination polymers, [Mn((R,R)Salcy)Fe(Tp)(CN)3∙H2O∙1/2CH3CN]n (1), [Mn((S,S)-Salcy)Fe(Tp)(CN)3∙H2O—1/2CH3CN]n (2), [Mn((R,R)Salcy)Fe(bpca)(CN)3—H2O]n (3), and [Mn((S,-Salcy)Fe(bpca)(CN)3∙H2O]n (4) [(R,R)-Salcy or (S,S)-Salcy = (R,R)- or (S,S)-N,N'-(1,2-cyclohexanediylethylene)bis(salicylideneiminato) dianion, Tp = tris(pyrazofyl)hydroborate, bpca = bis(2-pyddylcarbonyl)amidate anion], were synthesized using the mod8ied cyanometalate building blocks [Fe(L)(CN)3]- (L = Tp, bpca) and the chiral polydentate Schiff base manganese(lll) complex fragments. The circular dictiroism measurements showed Cotton effects of the opposite sign at the same wavelength for each pair of enantiomers. Magnetic property studies indicated that complexes 1 and 2 show not only intrachain but also interchain field-induced metamagnetic transitions from an antiferromagnetic to a ferromagnetic state and exhibit an antiferromagnetic tong-range ordering with a TN of 3.2 K, while enantiomers 3 and 4 are typical antiferromagnetic coupling compounds. Furthermore, complex 3 exhibits a ferroetectric behavior that relates to the polar point group C2, in which it crystallizes. [ABSTRACT FROM AUTHOR]

Spontaneous resolutions from an in situ reaction especially for a Sharpless reaction are really rare. Here we display a new pair of enantiomeric compounds Δ- and Λ-[Mn(4-tzba)(bpy)2·H2O](bpy)·3H2O (labeled as Δ-1 and Λ-1 respectively) (4-tzba = 4-tetrazolbenzoic acid; bpy = 2,2′-bipyridine) from a Sharpless reaction. They crystallized in the P212121 chiral space group and demonstrated strong second harmonic generation (SHG) responses and red photoluminescence property. The chiral metal conformations were captured by the introduction of the distorted bpy and the in situ synthesized 4-tzba ligands. The hydrogen bonds connecting the 4-tzba and central metal play a crucial role in the chirality transmission, as well as the donor-acceptor type SHG nonlinear response. [ABSTRACT FROM AUTHOR]

Although a number of acentric or chiral tetrazole complexes were synthesized from Sharpless reaction, there are no spontaneous resolution Cu(I)-tetrazole compounds from in situ [2 + 3] cycloaddition synthesis that have been reported before. The first enantiomers Δ- and Λ- of metal tetrazole compound [Cu(Tzmp)]n (1) (HTzmp = 3-tetrazolemethylpyridine) were obtained and isolated from in situ [2 + 3] cycloaddition reactions of a flexible organic nitrile (3-cyanomethylpyridine) with sodium azide in the presence of CuCl2 as the Lewis acid. Δ-1 and Λ-1 feature a homochiral helical coordination polymeric system and {4(4).6(2)} two-dimensional framework. The photoluminescence study suggests 1 exhibits strong green fluorescence in solid state with maximal emission peaks around 535 nm. Remarkably, the Δ- and Λ- of [Cu(Tzmp)]n (1) catalyzes the enantioselective Henry reaction with high yield (more than 96%) and certain enantioselectivity (up to 69%). [ABSTRACT FROM AUTHOR]