A comparative study of the decomposition of o-alkynyl-substituted aryl diazo ketones. Synthesis of polysubstituted .beta.-naphthols via arylketene intermediates
摘要:
The photochemical, thermal, and rhodium-catalyzed decomposition reactions of several closely related o-alkynyl or o-alkenyl alpha-diazoaceto- and propiophenone derivatives have been studied. The reaction outcome is markedly dependent upon the reaction conditions employed for nitrogen extrusion. Thermolysis or photolysis of o-alkynyl alpha-diazopropiophenone derivatives yields polysubstituted beta-naphthols. These products are derived from Wolff rearrangement of the initially formed carbene to give an aryl ketene which undergoes intramolecular cyclization onto the o-alkynyl substituent. In direct contrast to the thermal and photochemical results, Rh(II)-catalyzed decomposition yields products derived from direct attack of a rhodium carbenoid onto the tethered pi-system producing a vinyl carbenoid intermediate. Further reaction of the cyclized carbenoid with the starting diazo compound furnishes a vinyl indenone which undergoes a rapid intramolecular Diels-Alder reaction to produce a novel dimer whose structure was elucidated by an X-ray crystal analysis. Replacement of the methyl group on the diazo center with a sterically less demanding hydrogen atom was also found to play an important role in controlling the outcome of the Rh(II)-catalyzed reaction.
[EN] ISOCHROMENE DERIVATIVES AS PHOSPHOINOSITIDE 3-KINASES INHIBITORS<br/>[FR] DÉRIVÉS D'ISOCHROMÈNE UTILES EN TANT QU'INHIBITEURS DES PHOSPHOINOSITIDE 3-KINASES
申请人:CHIESI FARMA SPA
公开号:WO2015091685A1
公开(公告)日:2015-06-25
The invention relates to compounds inhibiting phosphoinositide 3-kinases (PI3K), to pharmaceutical compositions comprising them and therapeutic use thereofin the treatment of disorders associated with PI3K enzymes.
ISOCHROMENE DERIVATIVES AS PHOSHOINOSITIDE 3-KINASES INHIBITORS
申请人:CHIESI FARMACEUTICI S.p.A.
公开号:US20150166549A1
公开(公告)日:2015-06-18
Compounds of formula (I) described herein are useful for inhibiting phosphoinositide 3-kinases (PI3K) and the treatment of disorders associated with PI3K enzymes.
Cobaltcomplex/Zn systems effectively catalyze the reductive coupling of activated alkenes with alkynes in the presence of water to give substituted alkenes with very high regio- and stereoselectivity in excellent yields. While the intermolecular reaction of acrylates, acrylonitriles, and vinyl sulfones with alkynes takes place in the presence of CoI2(PPh3)2/Zn, the reaction of enones and enals with
Synthesis of 4-Selanyl- and 4-Tellanyl-1<i>H</i>-isochromen-1-ones Promoted by Diorganyl Dichalcogenides and Oxone
作者:Helen A. Goulart、José S. S. Neto、Angelita M. Barcellos、Krigor B. Silva、Maiara C. de Moraes、Raquel G. Jacob、Eder J. Lenardão、Thiago Barcellos、Gelson Perin
DOI:10.1021/acs.joc.1c00271
日期:2021.10.15
A new method was developed for the synthesis of 4-chalcogenyl-1H-isochromen-1-ones through the 6-endo-dig electrophilic cyclization of 2-alkynylaryl esters and diorganyl dichalcogenides under ultrasound irradiation. The reactions were performed under mild conditions, using Oxone as a green oxidant to promote the cleavage of the chalcogen–chalcogen bond in diorganyl diselenides and ditellurides to generate
We have developed a copper-catalyzedsubstitutionreaction of propargylic ammonium salts with aryl Grignard reagents. The reaction is stereospecific and α-regioselective and proceeds with exceptional functional group tolerance. Conveniently, a stable, inexpensive, and commercially available copper salt is used and no added ligand is required.