Facile synthesis of 4-acetyl-coumarins, -thiocoumarin and -quinolin-2(1H)-one via very high α-regioselective Heck coupling on tosylates
作者:Sergio Valente、Gilbert Kirsch
DOI:10.1016/j.tetlet.2011.04.033
日期:2011.7
An efficient synthesis of a series of methyl ketones at the C4 position of coumarins, coumarin-containing heterocycles and analogous scaffolds is reported via very high α-regioselective Heck coupling using tosylates and in very high yields. Although α-regioselectivity in Heck coupling can be obtained with triflates as substrates, tosylates are less toxic, less expensive and, importantly, more stable
AbstractOn irradiation (350 nm) in the presence of 2,3‐dimethylbuta‐1,3‐diene (8), 4‐(alk‐1‐ynyl)coumarins 1 afford mixtures of cyclobuta‐ and cycloocta‐annulated products 9 and 10, respectively. In contrast, the corresponding thiocoumarins 2 react with the same diene chemoselectively to give cyclohexa‐annulated products 11.
Light-Induced Coumarin Cyclopentannelation
作者:Marko Soltau、Maren Göwert、Paul Margaretha
DOI:10.1021/ol051952i
日期:2005.11.1
Whereas cyclopentenylcarbenes resulting from photocycloaddition of 4-alk-1-ynylcoumarins to 2,3-dimethylbut-2-ene undergo tandem cyclization to hitherto unknown tetracyclic (4-hetera)cyclopent[b, c]acenaphthylenes, the corresponding cyclopentenylnitrenes stemming from 4-cyanocoumarins and the same alkene are converted into tricyclic imines via H-abstraction.
Near Infrared Ray Activation Type Positive Resin Composition
申请人:Imai Genji
公开号:US20070259279A1
公开(公告)日:2007-11-08
A near infrared ray activation type positive resist composition comprising (A) a vinyl-based polymer having a monomer unit having an alkali-soluble group blocked by an ether having an alkenyl group next to an ether oxygen, (B) a photothermal converting substance generating heat by a light in the near infrared region, (C) a thermal acid generator generating an acid by heat, can provide a near infrared ray activation type positive resist composition which can be subjected to an exposure treatment in a complete bright room such as under a white light and the like, gives desired sensitivity and resolution, and of which baking treatment conditions can be relaxed or a baking treatment can be omitted, and a pattern formation method using the same.
Positive resist composition for recording medium master, and method of producing recording medium master and method of producing stamper using the same
申请人:Imai Genji
公开号:US20090045552A1
公开(公告)日:2009-02-19
Provided are a positive resist composition for recording medium master showing excellent plating resistance and adhesion to a base plate such as glass or the like characterized by containing a vinyl polymer which has a monomer unit having an alkali-soluble group blocked by an alkyl vinyl ether, and a method of producing a recording medium master or stamper using this positive resist composition.