68487-07-0

Upstream product

• 105-54-4 butanoic acid ethyl ester 
• 98-86-2 acetophenone 
• 75-16-1 methylmagnesium bromide 
• 1026561-05-6 1-[1-Ethoxy-1-(1-phenyl-1-trimethylsilanyloxy-ethyl)-allyl]-1H-benzotriazole 
• 109-74-0 propyl cyanide 
• 172846-87-6 3-(Benzotriazol-1-yl)-3-ethoxy-2-phenylpent-4-en-2-ol 
• 3848-24-6 2,3-hexanedione 
• 934-56-5 trimethyl(phenyl)stannane 
• 927-77-5 n-propylmagnesium bromide 

Relevant academic research and scientific papers

Titanium-catalyzed reductive umpolung reactions with a metal-free terminal reducing agent

A new method for titanium-catalyzed reductive umpolung reactions is reported that overcomes the traditional requirement for a stoichiometric metallic reductant. With N,N′-disilylated tetramethyldihydropyrazine as a potent organic reducing agent, reductive carbonyl-nitrile, enone-acrylonitrile and pinacol coupling reactions can be achieved in good yields and stereoselectivities. [Cp2TiI2] is a superior catalyst to [Cp2TiCl2], which is rationalized by a faster generation of the active catalyst [Cp2TiI]. A mechanism is proposed that is in agreement with the experimental results. Replacing zinc: A protocol for titanium(III)-catalyzed reductive umpolung reactions is presented that enables the title reactions in the presence of an N,N′-disilylated tetramethyldihydropyrazine as an organic sacrificial reducing agent. It is successfully applied to carbonyl-nitrile, enone-acrylonitrile and pinacol coupling reactions. A remarkable effect of the titanocene counterion renders titanocene diiodide a superior catalyst.

The cross-selective titanium(III)-catalysed acyloin reaction

A titanium(iii)-catalysed intermolecular reductive coupling of ketones or imines with nitriles is described, which gives direct access to α-hydroxylated and α-aminated ketones. This coupling reaction is cross-selective and a catalytic version of the classical acyloin condensation. A reaction mechanism that is supported by first DFT calculations is discussed. the Partner Organisations 2014.

Electroreductive acylation of aromatic ketones with acylimidazoles

The intermolecular reductive coupling of aromatic ketones with acylimidazoles was effected by electroreduction in the presence of chlorotrimethylsilane and gave α-trimethylsiloxy ketones and esters. The best result was obtained using Bu4NPF6 as a supporting electrolyte and a Pb cathode in THF. The α-trimethylsiloxy-containing products were transformed to the corresponding α-hydroxy ketones and esters by treatment with TBAF in THF. This method was also effective for the intramolecular reductive coupling of δ- and ε-keto acylimidazoles.

Rhodium-catalyzed addition of arylstannanes to carbon-heteroatom double bond

The addition of arylstannanes to the carbon-heteroatom double bond in the presence of a catalytic amount of a cationic rhodium complex ([Rh(cod)(MeCN)2]BF4) was examined. The reactions of aldehydes, α-dicarbonyl compounds, and N-substituted aldimines with the arylstannanes gave corresponding alcohols, α-hydroxy carbonyl compounds, and amines, respectively. An arylrhodium complex generated by the transmetalation with the arylstannane was probably the active catalytic species.

Novel Routes to Enol Ethers, Unsymmetrical Ketones, α-Bromoalkyl Ketones, 1,4-Diketones, 2-Ethoxy-2-cyclopenetenones, and α-Keto Enamines

Highly regioselectve SN2' reactions of adducts 6 (readily prepared by reactions of halides with the allyl anion 12 of 11) with Grignard reagents gave enol ethers 13, which were converted (in one-pot reactions from 11) into ketones 14 and α-bromoalkyl ketones 15 in good yields.The monoprotected 1,4-diketone derivative 16 (prepared by Michael addition of the allyl anion 12 with methyl vinyl ketone) was converted both into 1,4-diketones 18 and into protected γ-hydroxyalkyl ketone 20 by propenoyl, or to both functionalities.The allyl anion 12 with α-substituted acetic esters gave α-acylated adducts 24, which underwent in situ unfavored endo-trig cyclization upon treatment with NaH and secondary amines, to give 2-ethoxy-2-cyclopenetenones 27 and 28 and α-keto enamines 25 in good yield.The mechanism for the cyclization is discussed.