Efficient syntheses are described for the new bridging bis-phosphanes DPPN (4) and DPEN (5) built around the restricted rigidity of a 2,7-dialkoxynaphthalene backbone. These show marked preference for bridging pairs of metal atoms (PtII, Mo0) to form metallamacrocycles or oligomers. Single-crystal X-ray structure determinations of four dimeric complexes with PtII and Mo0 are reported. The dimeric platinum
THERMOSETTING ALKOXYSILYL COMPOUND HAVING TWO OR MORE ALKOXYSILYL GROUPS, COMPOSITION AND CURED PRODUCT COMPRISING SAME, USE THEREOF, AND METHOD FOR PREPARING ALKOXYSILYL COMPOUND
申请人:KOREA INSTITUTE OF INDUSTRIAL TECHNOLOGY
公开号:US20180155370A1
公开(公告)日:2018-06-07
The present invention relates to: a thermosetting alkoxysilyl compound (hereinafter, referred to as “alkoxysilyl compound”)having two or more alkoxysilyl groups showing excellent heat-resistance characteristics in a composite; a composition and a cured product comprising the same; a use thereof; and a method for preparing an alkoxysilyl compound. The composition of an alkoxysilyl compound, comprising a novel alkoxysilyl compound according to the present invention shows, in a composite, improved heat-resistance characteristics, i.e., an effect of decreasing the CTE of the composition of an alkoxysilyl compound and not showing a glass transition temperature (hereinafter, referred to as “Tg-less”). Further, the cured product comprising an alkoxysilyl compound according to the present invention shows excellent flame retardant properties due to the alkoxysilyl groups.
A process for preparing a polyhydric alcohol according to the invention comprises subjecting a polyhydric alcohol compound having protected hydroxy group(s) to microwave irradiation in the presence of basic compound(s) or acid(s) having an acid dissociation exponent (pKa) of −8 to 3 at 25° C. to remove the protecting groups of the hydroxy group of the polyhydric alcohol compound. The invention can provide an industrially advantageous process for preparing polyhydric alcohols by readily removing protecting group(s) from protected hydroxy group(s) of polyhydric alcohol compounds.
Diversity-Oriented Approach to Biologically Relevant Molecular Frameworks Starting with β-Naphthol and Using the Claisen Rearrangement and Olefin Metathesis as Key Steps
作者:Sambasivarao Kotha、Kalyaneswar Mandal、Arti Tiwari、Shaikh M. Mobin
DOI:10.1002/chem.200600540
日期:2006.10.25
A diversity-orientedapproach for the synthesis of various structurally different molecular frameworks from readily accessible and common precursors is described. A Claisen rearrangement followed by ring-closingmetathesis or ethylene-promoted ring-closing enyne metathesis has been utilized as the key synthetic transformation to generate naphthoxepine derivatives. The ring-closingmetathesis approach
Synthesis of bis-fused benzofuran derivatives by the implementation of palladium-mediated intramolecular cyclization is described. To our knowledge, this is the first report of the synthesis of bis-fused benzofuran by this protocol. Bisbenzoxepine and bisbenzoxocine derivatives were also synthesized by the application of two-directional ring-closing metathesis. palladium catalyst - Grubbs catalyst