A novel organocatalytic [3+2] annulation/oxidative aromatizationreaction of enals with 2-halophenols or β-naphthols is reported. This process enables chemo- and regioselective access to 2-arylbenzofuran-3-carbaldehydes without the use of transition metals or strong oxidants. Preliminary mechanistic studies reveal that an unprecedented, organocatalytic, direct α-arylation pathway is involved.
Palladium-catalyzed alkene-directed cross-coupling of aryliodide with another aryl halide through C-H arylation opens a unique avenue for unsymmetrical biaryl-derived molecules. However, homo-coupling of aryliodides often erodes the overall synthetic efficiency. Reported herein is a highly chemoselective Pd0 -catalyzed alkyne-directed cross-coupling of aryliodides with bromophenols, which was subsequently
Modular Assembly of Spirocarbocyclic Scaffolds through Pd<sup>0</sup>
-Catalyzed Intermolecular Dearomatizing [2+2+1] Annulation of Bromonaphthols with Aryl Iodides and Alkynes
A novel palladium(0)‐catalyzed dearomatizing [2+2+1] spiroannulation of 1‐bromo‐2‐naphthols with aryl iodides and alkynes was developed for the rapid assembly of spiro[indene‐1,1′‐naphthalen]‐2′‐ones. This three‐component cascade reaction was realized through consecutive Catellani‐type C−H activation, unsymmetrical biaryl coupling, alkyne migratory insertion, and arene dearomatization. The potential
Rapid assembly of fluorene-based spirocycles represents a highly significant but challenging task in organic synthesis. Reported herein is a novel Pd(0)-catalyzed [4+1] spiroannulation of simple o-iodobiaryls with bromonaphthols for the one-step construction of [4,5]-spirofluorenes in high yields with excellent functional group tolerance. Noteworthily, these valuable fluorene-based coumarin skeletons
Derivatives of naphthalene with comt inhibiting activity
申请人:——
公开号:US20040034011A1
公开(公告)日:2004-02-19
Compounds of formula (I′), wherein A, R
1
to R
3
and t are as defined in the disclosure, exhibit COMT enzyme inhibiting activity so that they are useful as COMT inhibitors.