ynamide carbozincation leading mainly to diverse 3-aryl enamides with mild reaction conditions and good functional-group tolerance has been developed. This reaction displays an excellent regio- and totalstereoselectivity and opens the way to appealing synthetic applications. Moreover, this approach allows the selective synthesis of biologically relevant 3,5-disubstituted oxazolone frameworks.
Preparation of Multisubstituted Enamides via Rhodium-Catalyzed Carbozincation and Hydrozincation of Ynamides
作者:Benoit Gourdet、Mairi E. Rudkin、Ciorsdaidh A. Watts、Hon Wai Lam
DOI:10.1021/jo901658v
日期:2009.10.16
Rhodium-catalyzed carbozincation of ynamides using diorganozinc reagents or functionalized organozinc halides is described. Using a tri(2-furyl)phosphine-modified rhodium catalyst, the reaction course is altered to hydrozincation when diethylzinc is employed as the organozinc reagent. Trapping of the alkenylzinc intermediates produced in these reactions in further functionalization reactions is possible. Collectively, these processes enable access to a range of multisubstituted enamides in stereo- and regiocontrolled fashion.
Nickel-catalyzed regio- and stereoselective hydrophosphinylation of internal ynamides with H-phosphinates
A method for the catalytic hydrophosphinylation of internal ynamides with H-phosphinates has been developed for the first time. The protocol employing the catalyst generated from NiBr2 and PPh3 could be applied to several types of ynamides and H-phosphinates, affording (E)-beta-aminovinylphosphinates in a highly regio- and stereoselective manner. (C) 2018 Elsevier Ltd. All rights reserved.
Copper-catalyzed hydrophosphinylation of terminal ynamides with H -phosphinates
A method for Cu(OAc)(2)-catalyzed hydrophosphinylation of ynamides was developed and applied to several types of terminal ynamides and H-phosphinates. The products were transformed into beta-ami-nophosphinates, which are useful for the preparation of biologically active compounds. (C) 2017 Elsevier Ltd. All rights reserved.
Zinc Chloride Mediated Synthesis of
<i>3H</i>
‐Oxazol‐2‐one and Pyrrolo‐oxazin‐1‐one from Ynamide
A simple zincchloridemediated cyclization of ynamidyl N‐carbamates or 2‐ynamidyl‐(hetero)arylcarboxylates is achieved under mild reaction conditions, leading to the synthesis of useful heterocyclic scaffolds, 3H‐oxazol‐2‐ones and pyrrolo‐oxazin‐1‐ones, with good yields.