Multifunctional substitution

Summary Multifunctional (meth)acrylate alkoxysilanes synthesized from commercially available acrylate compounds and mercapto-substituted alkoxysilanes or hydrosilanes are used as novel precursors for inorganic-organic copolymers. The alkoxysilyl groups are available for the formation of an inorganic Si-O-Si backbone by sol-gel processing. The (meth)acrylate groups allow the additional formation of organic polymer units by thermally or photochemically induced polymerisation reactions. 

Interestingly, the Fe2+ ion in the core can be easily removed by base, the complex dissociates and the individual polymer dimers can be analyzed. Block copolymers of 2-ethyl-2-oxazoline with other substituted oxazolines have also been made [121]. Ru2+(4,4 dichloromethyl-2,2 bipyridine)3 has also been used as the multifunctional initiator for the ATRP of styrene at 110°C [122], It is interesting to note that the Cu+ ions necessary for the polymerization reaction are solubilized via complexation with other bipyridine species. 

Yuan MS, Liu ZQ, Fang Q (2007) Donor-and-acceptor substituted truxenes as multifunctional fluorescent probes. J Org Chem 72 7915-22... 

Cyclohexadienones 61 and 64 are readily available from monoprotected hydro-quinones or para-substituted phenols, respectively. Conjugate additions to these symmetrical dienones result in desymmetrization of the prochiral dienone moieties, providing access to multifunctional chiral synthons in two steps from the aromatic precursors (Scheme 7.17) [72]. 

Chemoselectivity is often a major issue in the reduction of multifunctional organic substrates such as substituted conjugated enones. The corresponding unsaturated alcohols have found use as building blocks for pharmaceutically active molecules for example (i-amino-a-phenylethanol is used for the synthesis of (5-blockers which are the active molecules for controlling hypertension and other cardiac disorders. 

The conversion of DAMN into 2,3-dicyanopyrazines substituted in the 5-and 6-positions with various combinations of amino, cyano, chloro, and hydroxyl groups will be described in this section along with transformations of these initially formed materials into a variety of other multifunctional and fused ring pyrazines. 

Quite a wide variety of alkenes have been subjected to this carbene addition [148] the products are multifunctional small ring molecules which may not only be reduced to simple vinylcyclopropanes, but to various substituted cyclopropyl-acetylenes and cyclopropylideneacetates which are particularly useful and versatile building blocks for organic synthesis [155],... 

Abe, T. Suzuki, T. Sekiguchi, K. Hosokawa, S. Kobayashi, S. Stereoselective construction of a quaternary carbon substituted with multifunctional groups application to the concise synthesis of (+)-ethosuximide. Tetrahedron Lett. 2003, 44, 9303-9305. 

Aryloxide (phenolate) ligands provide rigid and versatile ancillary ligand sets in order to study the multifunctional reactivity of alkylaluminum and alkylmagnesium reagents toward Ln-OR moieties. Several types of symmetrically substituted phenolate ligands — summarized in Chart 4 — were employed for the synthesis of a variety of heterobimetallic lanthanide(III) and lanthanide(II) metal complexes. Alkylation reactions revealed the preferred... 

Because of the unique combination of mechanical, electrical, and thermal properties, the CNTs have been excellent candidates to substitute or complement the conventional nanofillers in the fabrication of multifunctional PNs. The first PNs using CNTs as the nanoadditive was reported in 1994.20 By far, the CNTs have been the second most investigated nanoadditives to reduce the flammability of the polymers through nanocomposite technology. A difficulty of the application of the CNTs in polymers is the dispersion of CNTs in the matrix polymer, and the high cost of the CNTs is another problem. 

Radiation Curable Reactive acrylates-vinyl 2EHA, NVP, etc Multifunctional di or triacrylates same as conventional but are usually substituted with acrylic-methacrylic acids 10-30% multifunctional acrylate 10-50% polymer 20-50% reactive solvent... 

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