Catalytic Enantioselective Simultaneous Control of Axial Chirality and Central Chirality in Allenes
作者:Jianxin Dai、Xinyu Duan、Jing Zhou、Chunling Fu、Shengming Ma
DOI:10.1002/cjoc.201800090
日期:2018.5
to report a protocol for preparation of chiral allenes with both central and axial chiralities via a catalyticasymmetricallenylation of different biologically or synthetically useful fluorinated or non‐fluorinated nucleophiles with readily available racemic allenes by using a single chiral ligand. An echoing between the centralchirality and axial chirality for the enantioselectivity was observed
Catalytic Nucleophilic Fluorination of Secondary and Tertiary Propargylic Electrophiles with a Copper-N-Heterocyclic Carbene Complex
作者:Li-Jie Cheng、Christopher J. Cordier
DOI:10.1002/anie.201506882
日期:2015.11.9
A catalytic method for the nucleophilicfluorination of propargylicelectrophiles is described. Our protocol involves the use of a Cu(NHC) complex as the catalyst and is suitable for the preparation of secondary and tertiarypropargylic fluorides without the formation of isomeric fluoroallenes. Preliminary mechanistic investigations suggest that fluorination proceeds via copper acetylides and that
The use of Br/Cl to promote regioselective gold-catalyzed rearrangement of propargylic carboxylates: an efficient synthesis of (1Z, 3E)-1-bromo/chloro-2-carboxy-1,3-dienes
作者:Yanzhao Wang、Biao Lu、Liming Zhang
DOI:10.1039/c0cc03669b
日期:——
A gold-catalyzed synthesis of 1-bromo/chloro-2-carboxy-1,3-dienes is developed using propargylic carboxylates containing halogenated alkynes as substrates. The reaction is highly diastereoselective, and the halogen atom at the alkyne terminus selectively promotes a 1,2-acyloxy migration. The diene products participate in the Diels–Alder and cross-coupling reactions.