From porous AlPO 4 to porous BIFs Reported here are a family of crystalline materials based on boron imidazolate frameworks (BIFs). It is demonstrated that the synthetic method, which is based on the crosslinking of various pre-synthesized boron imidazolates by monovalent cations (Li + and Cu + ), is capable of generating a large variety of open frameworks ranging from the 4-connected zeolitic sodalite type to the 3-connected chiral (10,3)-a type.

Reported here are two highly porous examples of MOCOFs, a new family of framework materials seamlessly integrating the coordinate bonds of metal-organic frameworks (MOFs) and covalent bonds of covalent organic framework materials (COFs). These two materials represent the lightest zeolite RHOs. Their synthesis is an extraordinary example in which the structure-directing effect of the substituent groups on the cross-linking imidazolyl ring strikes a perfect balance with their pore narrowing effect, leading to the creation of a very open zeolite RHO topology with highly accessible internal pores, characterized by a large surface area of 1818 m(2)/g and a high CO(2) storage capability as high as 35.6 cm(3)/g at 760 Torr and 273 K.

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Hydrosilylation of vinyl ferrocene with allylhydridopolycarbosilane was used to synthesize a processable hyperbranched polyferrocenylcarbosilane (HBPFCS).

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Bulky particles of TS‐1 zeolite (larger than 20 μm) are successfully collected by simple filtration after crystallization of TS‐1 zeolite in the presence of H2O2. Bulky TS‐1 (B‐TS‐1) has good stability under both ultrasonic conditions and in recycling of the catalyst. Nitrogen isotherms show that B‐TS‐1 has a larger mesopore volume (0.55 cm3 g−1) than conventional TS‐1 nanocrystals (N‐TS‐1; less than 300 nm) obtained from high‐speed centrifugation (0.28 cm3 g−1). In catalytic hydroxylation of phenol with H2O2, both fresh (25 %) and recycled B‐TS‐1 (24 %) show similar high activities to N‐TS‐1 (28 %). B‐TS‐1 was further characterized by X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, UV/Vis spectroscopy, and other techniques. The results suggest that bulky particles of B‐TS‐1 were formed by strong interactions of the nanocrystals with each other in the synthesis of TS‐1 zeolite. Such unique structural features might be responsible for the high stability of the bulky particles, large mesopore volume, and high catalytic activities in phenol hydroxylation, as well as the collection of B‐TS‐1 from a simple filtration route.

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Low connectivity (four-or three-connectivity) of the basic structural building block is closely associated with the open architecture and porosity in 3D framework materials. The synthetic development of low-connectivity frameworks with new composition and topology continues to attract much attention, because applications of such materials depend on the unique composition or topology of each material. [1][2][3][4][5][6] Currently, the synthesis of metal-organic frameworks (MOFs) is an active research area. [1,7] The vast majority of new microporous materials synthesized in the past decade belong to this family. [8][9][10][11][12][13] Among numerous known MOFs, a family of materials that closely resemble zeolite topologies, are those based on divalent metal (M 2+ ) imidazolates (im À ) in which M 2+ and im À ions replace zeolite Si 4+ (Al 3+ ) and O 2À ions, respectively, resulting in the general framework composition [M(im) 2 ], just like SiO 2 . [8][9][10][11] The success in generating new zeolitic topologies is attributed to structure-directing effects of imidazolate ligands and other conditions, such as solvents.Herein we demonstrate a versatile synthetic method capable of generating a large family of low-connectivity framework materials. This method is based on the crosslinking of various presynthesized boron imidazolate complexes with monovalent cations (e.g., Li + and Cu + ) into extended frameworks. One advantage of this method is that it allows the use of ultralight chemical elements (i.e., Li and B) as framework vertices. Furthermore, unlike the zinc imidazolate system, in which it is difficult to presynthesize threeconnected Zn(im) 3 À units, both four-connected B(im) 4 À and three-connected HB(im) 3 À can be readily synthesized prior to solvothermal synthesis (Scheme 1), thus further increasing the diversity of materials accessible through this method. For the creation of four-connected topologies, our strategy is reminiscent of the strategy that led to the discovery of microporous AlPO 4 by analogy with porous silica. [2] Just as Al 3+ and P 5+ ions can replace two Si 4+ sites in a porous silicalite, Li + and B 3+ ions can replace two Zn 2+ sites in a [Zn(im) 2 ] framework.A total of eleven boron imidazolate framework materials have been made (Table 1). In addition to four-connected topologies, three-connected and mixed (3,4)-connected 3D framework topologies have also been realized. These materials exhibit eight distinct topological features (Table 1). Three particularly interesting materials are the unprecedented fourconnected framework materials (BIF-1-Li, BIF-2-Li, and BIF-3-Li) based on the lightest possible tetrahedral nodes in the Periodic Table, Li and B (excluding Be, which is not studied herein because of its toxicity).BIF-1-Li exhibits a 3D tetrahedral framework in which each Li + or B 3+ ion is connected to four imidazolyl ligands to create a SiO 4 -like tetrahedron (i.e., Li(im) 4 or B(im) 4 ; Figure 1 a). Each im À linker bridges one Li + center and one B 3+ center, with Li···B distances ...