Sulfonated Microporous Organic−Inorganic Hybrids as Strong Bronsted Acids<sup>1</sup>
作者:Zhike Wang、Joy M. Heising、Abraham Clearfield
DOI:10.1021/ja030226c
日期:2003.8.1
It has been discovered that the use of excess zirconium in reactions with 4,4'-biphenyl and 4,4'-terphenylbis(phosphonic acid) in DMSO or DMSO-ethanol mixtures produces microporous inorganic-organic hybrids. Surface areas of 400 m(2)/g and pore sizes in the range of 10-20 A in diameter are routinely obtained. These materials are readily sulfonated with SO(3) under pressure to yield strong Bronsted
Mesoporous crystalline solid compound of a diphosphonate/phosphite of a
申请人:Eniricerche S.p.A.
公开号:US05166380A1
公开(公告)日:1992-11-24
The present invention discloses a compound comprising a diphosphonate/phosphite of a tetravalent metal: M[(O.sub.3 P--R--PO.sub.3).sub.1-(x+y) (HPO.sub.3).sub.2X (O.sub.3 P--R--PO.sub.3 H.sub.2).sub.2y ] (where M, R, x and y have the meaning given in the description), in the form of a crystalline solid with an alpha-type lamellar structure with a distance between layers of 7.4 to 20.ANG. (depending on the dimensions of radical R), a BET surface area of 250 to 400m.sup.2 /g, and porosity within the mesopore range, with at least 50% of the pores measuring 20 to 30.ANG.. The compound, depending on the radical R used, may or may not have microporosity in the region between layers. Such a diphosphonate/phosphite of a tetravalent metal is obtained by reaction between diphosphonic acid, phosphorous acid and an oxyhalide of a tetravalent metal, in a solvent comprising dimethyl-sulphoxide/water containing hydrofluoric acid.
The crystal structure of the title compound, C12H12O6P2, displays two different regions alternating along the a axis: a hydrogen- bonded region encompassing the end- positioned phosphonic acid groups and a hydrophobic region formed by the aromatic spacers. The asymmetric unit contains only half of the biphenyl- 4,4'- diphosphonic acid ( 4,4'- bpdp) molecule, which is symmetric with an inversion centre imposed at the mid- point between the two aromatic rings. The periodic organization of the molecules is controlled by two strong O-H center dot center dot center dot O interactions between the phosphonic acid sites. Weak C-H center dot center dot center dot pi interactions are established in the aromatic regions.
POLYESTER POLYMERIZATION CATALYST AND METHOD FOR PRODUCING POLYESTER USING SAME