Catalytic Enantioselective Intermolecular Hydroacylation: Rhodium-Catalyzed Combination of β-S-Aldehydes and 1,3-Disubstituted Allenes
摘要:
A rhodium(I) catalyst incorporating the Me-DuPhos ligand promotes enantioselective intermolecular hydroacylation between P-S-aldehydes and 1,3-disubstituted allenes. The nonconjugated enone products are obtained in good yields and with high enantioselectivities.
Gold‐Catalyzed One‐Pot Synthesis of 1,3‐Disubstituted Allenes from Benzaldehydes and Terminal Alkynes
作者:Danilo M. Lustosa、Simon Clemens、Matthias Rudolph、A. Stephen K. Hashmi
DOI:10.1002/adsc.201900824
日期:2019.11.5
A new and facile one‐pot synthesis of 1,3‐disubstituted allenes, using cheap and readily available terminal alkynes, benzaldehyde derivatives and morpholine, was developed. A small library of 20 allenes demonstrates a broad applicability, with yields up to 86%. Isotopic‐labelling and cross‐over experiments strongly indicate that our reaction proceeds via a two‐step A3‐coupling followed by a 1,5‐hydrogen
Highly Regioselective Synthesis of Trisubstituted Allenes via Lithiation of 1-Aryl-3-alkylpropadiene, Subsequent Transmetalation, and Pd-Catalyzed Negishi Coupling Reaction
作者:Jinbo Zhao、Yu Liu、Shengming Ma
DOI:10.1021/ol8001909
日期:2008.4.1
A novel methodology for the synthesis of trisubstituted allenes is reported. Lithiation of 1-aryl-3-alkylpropadienes and subsequent transmetalation with zinc bromide followed by Pd-catalyzed Negishi couplingreactions with halides afforded the corresponding trisubstituted allenes in a highly regioselective fashion with moderate to excellent yields. A plausible regioselective lithiation mechanism was