Diversity-Oriented Synthesis of Spiropentadiene Pyrazolones and 1H -Oxepino[2,3-c ]pyrazoles from Doubly Conjugated Pyrazolones via Intramolecular Wittig Reaction

Organic Letters
Pankaj V KhairnarWenwei Lin

Abstract

An efficient method for the diversity-oriented synthesis of spiropentadiene pyrazolones and 1H-oxepino[2,3-c]pyrazoles is reported. The methodology attributes O-acylation of phosphorus zwitterions which were formed by a tandem phospha-1,6-addition of PBu3 to α,β,γ,δ-unsaturated pyrazolones, further generating betaine intermediates that preferentially resulted in the aforementioned cyclic products in a diversity-oriented manner. The mechanistic investigations revealed that formation of the betaines is the key step to provide the products via an intramolecular Wittig reaction or an unprecedented δ-C-acylation/cyclization/Wittig reaction.

References

Dec 25, 2003·Angewandte Chemie·Martin D Burke, Stuart L Schreiber
Aug 30, 2008·Bioorganic & Medicinal Chemistry·Daniele CastagnoloMaurizio Botta
Aug 24, 2010·Chemical Communications : Chem Comm·Xavier CompanyóRamon Rios
Sep 25, 2010·Bioorganic & Medicinal Chemistry Letters·Victor HadiKyung Woon Jung
Sep 25, 2010·Nature Communications·Warren R J D GallowayDavid R Spring
Aug 16, 2011·Organic & Biomolecular Chemistry·Alex ZeaRamon Rios
Aug 16, 2013·Chemical Communications : Chem Comm·Chia-Jui LeeWenwei Lin
Dec 10, 2013·Journal of the American Chemical Society·Andrés SeoaneMoisés Gulías
May 14, 2014·Journal of the American Chemical Society·Andrés SeoaneMoisés Gulías
Jul 17, 2015·Chemical Communications : Chem Comm·Pankaj ChauhanDieter Enders
Dec 18, 2015·Angewandte Chemie·Daniel HackDieter Enders
Jun 29, 2018·Chemical Society Reviews·Aishun DingRamon Rios
Sep 19, 2018·Chemical Communications : Chem Comm·Siyuan LiuBaomin Wang
Sep 28, 2018·Chemical Reviews·Hongchao GuoOhyun Kwon
Dec 1, 2019·Bioorganic & Medicinal Chemistry Letters·Lei WangChunquan Sheng

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.

Related Papers

Práctica odontológica
Práctica odontológica
Arquivos brasileiros de oftalmologia
J PESCADOR
© 2022 Meta ULC. All rights reserved