Access to β‐Ketonitriles through Nickel‐Catalyzed Carbonylative Coupling of α‐Bromonitriles with Alkylzinc Reagents
作者:Aske S. Donslund、Karoline T. Neumann、Nicklas P. Corneliussen、Ebbe K. Grove、Domenique Herbstritt、Kim Daasbjerg、Troels Skrydstrup
DOI:10.1002/chem.201902206
日期:2019.7.25
Herein, we report a nickel‐catalyzed carbonylative coupling of α‐bromonitriles and alkylzinc reagents with near stoichiometric carbon monoxide to give β‐ketonitriles in good yields. The reaction is catalyzed by a readily available and stable nickel(II) pincercomplex. The developed protocol tolerates substrates bearing a variety of functional groups, which would be problematic or incompatible with
Stereocontrolled Synthesis of the DE Ring System of the Marine Alkaloid Upenamide
作者:Kurt Kiewel、Zhushou Luo、Gary A. Sulikowski
DOI:10.1021/ol051993e
日期:2005.11.1
[reaction: see text] A stereocontrolled synthesis of the DE fragment (2) of the marine alkaloid upenamide (1) is described. The synthesis proceeds in 12 steps from caprolactone (10) and 20-25% overall yield.
A Mild, Palladium-Catalyzed Method for the Dehydrohalogenation of Alkyl Bromides: Synthetic and Mechanistic Studies
作者:Alex C. Bissember、Anna Levina、Gregory C. Fu
DOI:10.1021/ja306323x
日期:2012.8.29
accomplish palladium-catalyzed dehydrohalogenations of alkyl bromides to form terminal olefins. We have applied this method, which proceeds in excellent yield at room temperature in the presence of a variety of functional groups, to a formal total synthesis of (R)-mevalonolactone. Our mechanistic studies have established that the rate-determining step can vary with the structure of the alkyl bromide and
We have developed a one-pot method for the direct intermolecular reductive hydroxyalkylation or alkylation of amines using lactones or esters as the hydroxyalkylating/alkylating reagents. The method is based on the in situ amidation of lactones/esters with DIBAL-H–amine complex (for primary amines) or DIBAL-H–amine hydrochloride salt complex (for secondary amines), followed by reduction of the amides
Kinetic Resolution of Tertiary Allylic Alcohols: Highly Enantioselective Access to Cyclic Ethers Bearing an α-Tetrasubstituted Stereocenter
作者:Chao-Huan Zhang、Qing Gao、Meng Li、Jian-Fei Wang、Chuan-Ming Yu、Bin Mao
DOI:10.1021/acs.orglett.1c01110
日期:2021.5.21
A chiral phosphoric acid-catalyzed kinetic resolution of tertiary allylicalcohols was developed to provide structurally valuable enantioenriched 2,2-disubstituted tetrahydrofurans, tetrahydropyrans, and oxepane. A variety of tertiary allylicalcohols were resolved with selectivity factors of ≤120. A tertiary allylic carbocationic intermediate mediates the enantioselective intramolecular substitution