17684-12-7

Upstream product

• 65127-37-9 2-methyl-3,3-diphenyl-acrylic acid ethyl ester 
• 119-61-9 benzophenone 
• 34757-17-0 ethyl 2,2-dibromopropanoate 
• 778-66-5 1,1-diphenyl-1-propene 
• 124-38-9 carbon dioxide 
• 40662-79-1 (2,6-di-t-butyl)-phenyl propanoate 
• 72959-50-3 2,6-di-tert-butyl-4-methylphenyl propionate 
• 73198-88-6 2',6'-bis(1,1-dimethylethyl)-4'-methoxyphenyl propanoate 
• 40662-80-4 2,4,6-tri-tert-butylphenyl propionate 
• 100-52-7 benzaldehyde 
• 13411-45-5 trimethyl(2-phenyl-1,3-dithian-2-yl)silane 
• 5908-41-8 benzoyltrimethylsilane 
• 591-50-4 iodobenzene 
• 665004-97-7 (Z)-2-methyl-3-trimethylsilyl-3-phenylpropenoic acid 

Downstream Products

• 5292-20-6 α-methyl-β,β-diphenylpropionic acid 
• 13304-52-4 2-methyl-3-phenylinden-1-one 

Relevant academic research and scientific papers

Practical synthesis of ynolate anions: Naphthalene-catalyzed reductive lithiation of α,α-dibromo esters

Reductive lithiation of α,α-dibromo esters using lithium naphthalenide afforded ester dianions leading to ynolate anions in good yields. Naphthalene-catalyzed reductive lithiation was also accomplished. This is a convenient, economical and practical method for the preparation of ynolate anions.

Synthesis of Ynolates via Double Deprotonation of Nonbrominated Esters

Herein, we report a double deprotonation method used for the preparation of ynolates starting from nonbrominated 2,6-di-tert-butylphenyl esters. The current method is superior to the previously described double lithium/halogen exchange approach because easily accessible starting materials are used. This method will be especially useful for preparation of ynolates bearing functional groups in organic synthesis.

EtAlCl2/2,6-Disubstituted Pyridine-Mediated Carboxylation of Alkenes with Carbon Dioxide

α-Arylalkenes and trialkyl-substituted alkenes undergo carboxylation with CO2 in the presence of EtAlCl2 and 2,6-dibromopyridine to afford the corresponding α,β- and/or β,γ-unsaturated carboxylic acids. This reaction is suggested to proceed via the electrophilic substitution of EtAlCl2 with the aid of the base, followed by the carbonation of the resulting ate complex. This reaction can be applied to terminal dialkylalkenes by using a mixture of 2,6-di-tert-butylpyridine and 2,6-dibromopyridine.

Generation of ynolates via reductive lithiation using flow microreactors

A new method has been developed for the generation and subsequent reaction of ynolates in a micro flow reactor system. This new procedure allowed for ynolates to be prepared at 0 C or ambient temperature within 1 min via a reductive lithiation reaction, whereas the corresponding batch processes generally require low temperature control and extended reaction times of up to 1 h. The resulting ynolates were applied to the olefination of carbonyl compounds, with the reactions reaching completion in a much shorter reaction time in the continuous flow reactor than the batch reactor. These results highlight the practical utility of the ynolate reaction, and represent the first reported example of the use of lithium naphthalenide in a flow microreactor, which would contribute to progress of the flash chemistry.

Palladium-catalyzed fluoride-free cross-coupling of intramolecularly activated alkenylsilanes and alkenylgermanes: Synthesis of tamoxifen as a synthetic application

We have demonstrated that intramolecular hypercoordination of a carboxylic acid is a powerful activation strategy for the palladium-catalyzed cross-coupling reaction of trialkyl(vinyl)silanes and trialkyl(vinyl)germanes under fluoride-free conditions. Z-β-Trialkylsilyl- and Z-β- trialkylgermylacrylic acids, synthesized stereoselectively by olefination with ynolates, are highly stable and useful reagents for cross-coupling with a variety of aryl iodides to provide tetrasubstituted olefins possessing different carbon substituents in a stereocontrolled and diversity-oriented manner. An application to a stereoselective synthesis of (Z)-tamoxifen is also reported. Copyright

Stereoselective olefination of unfunctionalized ketones via ynolates

Ynolates react with ketones at room temperature to afford α,β,β,-trisubstituted acrylates (tetra-substituted olefins) with 2:1-8:1 geometrical selectivities. This can be regarded as a new olefination reaction of ketones giving tetrasubstituted olefins in good yield, even in the case of sterically hindered substrates. The reaction mechanism involves cycloaddition of ynolates with a carbonyl group and subsequent thermal electrocyclic ring-opening of the resulting β-lactone enolates. The stereoselectivity is determined in the ring-opening, which is regulated by torquoselectivity. In this paper, we describe the scope and limitations of olefination of ketones via ynolates and discuss the stereocontrol mechanism.