Two Chiral Metal Complex Templated Aluminoborates Constructed from Three Types of Oxoboron Clusters

The two acentric aluminoborates (ABOs) [M(dap)3]2{Al[B5O7(OH)3][B5O8(OH)2][B6O9(OH)2]} (M and dap represent Co(1)/Ni(2) and 1,2-diaminopropane, respectively) templated by chiral metal complexes (CMCs) have been solvothermally synthesized. The isostructural 1 and 2 crystallize in the chiral space group P21. Both feature unprecedented 2D wavelike layers built by three kinds of oxoboron (B-O) clusters ([B5O7(OH)3]2-, [B5O8(OH)2]3-, and [B6O9(OH)2]2-) and AlO4 tetrahedra. In the frameworks of 1 and 2, AlO4 and [B6O9(OH)2]2- units are strictly alternating into 1D chains. Further, [B5O8(OH)2]3- clusters link adjacent chains to form 2D wavelike layers. In addition, the [B5O7(OH)3]2- units as the hanging clusters are supported on two sides of the wavelike layers through AlO4 groups, resulting in the first example of a wavelike layer ABO composed of three kinds of B-O clusters and four types of channels. 1 and 2 display second-harmonic generation (SHG) signals about ∼1.3 and ∼0.93 times that of KH2PO4 (KDP) and belong to the class of wide-band-gap semiconductors.