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. 2022 May 11;144(18):7983-7987.
doi: 10.1021/jacs.2c02960. Epub 2022 Apr 27.

Ir-Catalyzed Asymmetric Allylic Alkylation of Dialkyl Malonates Enabling the Construction of Enantioenriched All-Carbon Quaternary Centers

Farbod A Moghadam  1 , Elliot F Hicks  1 , Zachary P Sercel  1 , Alexander Q Cusumano  1 , Michael D Bartberger  2 , Brian M Stoltz  1
Affiliations

Ir-Catalyzed Asymmetric Allylic Alkylation of Dialkyl Malonates Enabling the Construction of Enantioenriched All-Carbon Quaternary Centers

Farbod A Moghadam et al. J Am Chem Soc. .

Abstract

An enantioselective iridium-catalyzed allylic alkylation of malonates with trisubstituted allylic electrophiles to form all-carbon quaternary stereocenters is reported. This reaction proceeds at ambient temperature and enables the preparation of a wide range of enantioenriched products in up to 93% yield and 97% ee. The quaternary products can be readily converted to several valuable building blocks such as vicinal quaternary products and β-quaternary acids.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1.
Figure 1.
Construction of all-carbon quaternary centers via Ir-catalyzed allylic alkylation.
Scheme 1.
Scheme 1.
Nucleophile and Aryl Electrophile Investigationa aReactions conducted at 0.1 mmol scale, with 1 equiv of both nucleophile and electrophile. bYield determined by 1H NMR relative to a CH2Br2 internal standard.
Scheme 2.
Scheme 2.
Alkyl-substituted Allylic Electrophilesa aYields determined by CH2Br2 1H NMR standard. Reactions performed at 0.1 mmol scale.
Scheme 3.
Scheme 3.
Product Diversification
Scheme 4.
Scheme 4.
Formal Asymmetric Synthesis of Sporochnols A-C
See this image and copyright information in PMC

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