Synthesis of α-methyl ketones by a selective, iridium-catalyzed cyclopropanol ring-opening reaction

Ziegler, Daniel T.; Steffens, Andrew M.; Funk, Timothy W.

doi:10.1016/j.tetlet.2010.10.067

Cited by 20 publications

(9 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Since 144 is prepared from the corresponding ketone through a Simmons–Smith reaction sequence, this overall transformation can be envisioned as a selective monomethylation of a ketone. This isomerization can also be performed using catalytic iridium or stoichiometric magnesium . Ring‐opening is selective for generating the least‐substituted, less anionic homoenolate.…”

Section: Homoenolates As Nucleophilic Reagentsmentioning

confidence: 99%

Modern Developments in the Chemistry of Homoenolates

Mills

Rousseaux

2018

Eur J Org Chem

View full text Add to dashboard Cite

Homoenolates are unique synthetic intermediates which display umpolung reactivity. Homoenolates and homoenolate equivalents like cyclopropanols have seen a recent surge in popularity due to their particular utility for accessing β‐functionalized carbonyl derivatives. This popularity has been enabled by the development of protocols for facile access to cyclopropanols and homoenolates from a variety of readily available starting materials. This microreview will highlight common strategies for generating cyclopropanols and metal homoenolates, as well as procedures for homoenolate functionalization, with a particular emphasis on protocols that have appeared after 2003. As an amphoteric molecule, two main reactivity modes have been established: the homoenolate reacts as a carbon nucleophile for β‐functionalization reactions and/or as a carbonyl electrophile, a strategy which has only emerged in the past few years. This microreview will highlight the use of homoenolates as convenient intermediates for accessing especially challenging motifs. The use of homoenolate chemistry in the context of natural product and pharmaceutical synthesis will also be presented.

show abstract

Section: Homoenolates As Nucleophilic Reagentsmentioning

confidence: 99%

Modern Developments in the Chemistry of Homoenolates

Mills

Rousseaux

2018

Eur J Org Chem

View full text Add to dashboard Cite

show abstract

“…Wird dieses Intermediat wiederum mit CuCN⋅2 LiCl und Allylbromid versetzt, so entsteht das Keton 45 mit vollständig kohlenstoffsubstituiertem Stereozentrum und dem Enantiomerenverhältnis des Ausgangsmaterials (Schema ) 54. Desweiteren sind auch Iridiumkatalysatoren wie [{Cp*IrCl 2 } 2 ] in der Lage, hocheffizient Cyclopropanole in α‐Alkylketone zu überführen 56…”

Section: C‐c‐bindungsaktivierung Von Cyclopropanenunclassified

Fast and Effective Turn‐on Paper‐based Phosphorescence Biosensor for Detection of Glucose in Serum

Chen

Tsai

Zeng

et al. 2016

J Chinese Chemical Soc

View full text Add to dashboard Cite

In this study, a turn‐on paper‐based optical analytical system with a rapid, sensitive and quantitative response for glucose was developed. The luminescence sensing material, crystalline iridium(III)‐Zn(II) coordination polymers, or Ir‐Zne, was grown electrochemically on stainless steel mesh and then deposited on filter paper. This sensing substrate was subsequently built up under glucose oxidase encapsulated in hydrogel and then immobilized on egg membrane with the layer‐by‐layer method. Once the glucose solution was dropped onto the paper, the oxygen content was depleted simultaneously with a concomitant increase in the phosphorescence of Ir‐Zne. The detection limit for glucose was 0.05 mM. The linear dynamic range for the determination of glucose was 0.05–8.0 mM with a correlation coefficient (R2) of 0.9956 (y=68.11 [glucose]−14.72). The response time was about 0.12 s, and the sample volume was less than 5 μL. The effects of mesh size, buffer concentration, pH, enzyme concentration, temperature, and interference, and the stability of the biosensor, have also been studied in detail. Finally, the biosensor was successfully applied to the determination of glucose in human serum.

show abstract

“…[54] Similarly, the iridium catalyst [{Cp*IrCl 2 } 2 ] transformed selectively substituted cyclopropanols into a-alkyl ketones. [56] Clearly, the direct treatment of cyclopropanol 46, readily accessible through the Kulinkovitch cyclopropanation reaction, [40] with diethylzinc and a copper salt should also result in the formation of the zinc (or copper) homoenolate 47 through the selective ring-opening of the metal cyclopropanolate. In situ trapping leads to functionalized adducts 48 (Scheme 19).…”

Section: Carbon-carbon Bond Activation Of Cyclopropanesmentioning

confidence: 99%

Selective Carbon–Carbon Bond Cleavage for the Stereoselective Synthesis of Acyclic Systems

et al. 2014

View full text Add to dashboard Cite

Most of the efforts of organic chemists have been directed to the development of creative strategies to build carbon-carbon and carbon-heteroatom bonds in a predictable and efficient manner. In this Review, we show an alternative approach where challenging molecular skeletons could be prepared through selective cleavage of carbon-carbon bonds. We demonstrate that it has the potential to be a general principle in organic synthesis for the regio-, diastereo-, and even enantioselective preparation of adducts despite the fact that C-C single bonds are among the least reactive functional groups. The development of such strategies may have an impact on synthesis design and can ultimately lead to new selective and efficient processes for the utilization of simple hydrocarbons.

show abstract

Synthesis of α-methyl ketones by a selective, iridium-catalyzed cyclopropanol ring-opening reaction

Cited by 20 publications

References 38 publications

Modern Developments in the Chemistry of Homoenolates

Modern Developments in the Chemistry of Homoenolates

Fast and Effective Turn‐on Paper‐based Phosphorescence Biosensor for Detection of Glucose in Serum

Selective Carbon–Carbon Bond Cleavage for the Stereoselective Synthesis of Acyclic Systems

Contact Info

Product

Resources

About