Synthesis, Crystal Structure and Thermal Behavior of Co(en) 3 [B 4 O 5 (OH) 4 ]Cl·3H 2 O and [Ni(en) 3 ][B 5 O 6 (OH) 4 ] 2 ·2H 2 O

Two novel transition‐metal complex templated borates containing crystalline water, Co(en) 3 [B 4 O 5 (OH) 4 ]Cl·3H 2 O ( 1 ) and [Ni(en) 3 ][B 5 O 6 (OH) 4 ] 2 ·2H 2 O ( 2 ), have been synthesized hydrothermally and characterized by elemental analysis, single crystal X‐ray diffraction, FT‐IR spectroscopy, and TGA. The crystal structure of compound 1 is characterized mainly by forming a 3D supramolecular network through four kinds of hydrogen bonds, O–H···O, O–H···Cl, N–H···Cl and N–H···O, among all components of Co(en) 3 3+ , [B 4 O 5 (OH) 4 ] 2− , Cl − and H 2 O. The crystal structure of compound 2 is characterized by forming a 3D supramolecular framework with large channels along axis a through O–H···O hydrogen‐bonding among the [B 5 O 6 (OH) 4 ] − anions, in which the templating [Ni(en) 3 ] 2+ cations and crystalline water molecules are located.