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Literature DB >> 31361145

Phenolic Oxidation Using H₂O₂ via in Situ Generated para-Quinone Methides for the Preparation of para-Spiroepoxydienones.

Michael F McLaughlin¹, Elisabetta Massolo¹, Thomas A Cope¹, Jeffrey S Johnson¹.

Abstract

Phenols are attractive starting materials for the preparation of highly substituted cyclohexane rings via dearomative processes. Herein we report an efficient preparation of dearomatized 1-oxaspiro[2.5]octa-4,7-dien-6-ones (para-spiroepoxydienones) via the nucleophilic epoxidation of in situ generated para-quinone methides from 4-(hydroxymethyl)phenols using aqueous H2O2. The developed protocol bypasses the need for stoichiometric bismuth reagents or diazomethane, which are frequently deployed for p-spiroepoxydienone preparation. The p-spiroepoxydienones are further elaborated in numerous downstream complexity-building transformations.

Entities: Chemical Disease Species

Year: 2019 PMID： 31361145 PMCID： PMC6717626 DOI： 10.1021/acs.orglett.9b02372

Source DB: PubMed Journal: Org Lett ISSN： 1523-7052 Impact factor: 6.005

19 in total

1. Efficient generation of ortho-quinone methide: application to the biomimetic syntheses of (±)-schefflone and tocopherol trimers.

Authors: Daohong Liao; Houhua Li; Xiaoguang Lei
Journal: Org Lett Date: 2011-11-02 Impact factor: 6.005

2. Enantioselective synthesis of hindered cyclic dialkyl ethers via catalytic oxa-Michael/Michael desymmetrization.

Authors: Michael T Corbett; Jeffrey S Johnson
Journal: Chem Sci Date: 2013-07-01 Impact factor: 9.825

3. Stereoselectivity control by oxaspiro rings during Diels-Alder cycloadditions to cross-conjugated cyclohexadienones: the syn oxygen phenomenon.

Authors: Katsuo Ohkata; Yukiko Tamura; Brandon B Shetuni; Ryukichi Takagi; Wataru Miyanaga; Satoshi Kojima; Leo A Paquette
Journal: J Am Chem Soc Date: 2004-12-29 Impact factor: 15.419

Phenolic Oxidation Using H₂O₂ via in Situ Generated para-Quinone Methides for the Preparation of para-Spiroepoxydienones.

1. Efficient generation of ortho-quinone methide: application to the biomimetic syntheses of (±)-schefflone and tocopherol trimers.

2. Enantioselective synthesis of hindered cyclic dialkyl ethers via catalytic oxa-Michael/Michael desymmetrization.

3. Stereoselectivity control by oxaspiro rings during Diels-Alder cycloadditions to cross-conjugated cyclohexadienones: the syn oxygen phenomenon.

4. Concise and enantioselective synthesis of the aminocyclitol core of hygromycin A.

5. Substituents on quinone methides strongly modulate formation and stability of their nucleophilic adducts.

6. Isolation and structure elucidation of three neo-clerodane diterpenes from Teucrium fruticans L. (LABIATAE).

Review 7. Dearomatization strategies in the synthesis of complex natural products.

8. Catalytic asymmetric dearomatization reactions.

9. 1,6-Conjugated Addition-Mediated [2+1] Annulation: Approach to Spiro[2.5]octa-4,7-dien-6-one.

Review 10. The Emergence of Quinone Methides in Asymmetric Organocatalysis.

1. Unraveling Reversible DNA Cross-Links with a Biological Machine.

2. Directing Quinone Methide-Dependent Alkylation and Cross-Linking of Nucleic Acids with Quaternary Amines.

3. Chemoselective oxidative generation of ortho-quinone methides and tandem transformations.