86863-93-6Relevant academic research and scientific papers
A flow microreactor system enables organolithium reactions without protecting alkoxycarbonyl groups
Nagaki, Aiichiro,Kim, Heejin,Moriwaki, Yuya,Matsuo, Chika,Yoshida, Jun-Ichi
supporting information; experimental part, p. 11167 - 11177 (2010/11/04)
A flow microreactor system consisting of micromixers and microtube reactors provides an effective tool for the generation and reactions of aryllithiums bearing an alkoxycarbonyl group at para-, meta-, and ortho-positions. Alkyl p- and m-lithiobenzoates were generated by the I/Li exchange reaction with PhLi. The Br/Li exchange reactions with sBuLi were unsuccessful. Subsequent reactions of the resulting aryllithiums with electrophiles gave the desired products in good yields. On the other hand, alkyl o-lithiobenzoates were successfully generated by the Br/ Li exchange reaction with sBuLi. Subsequent reactions with electrophiles gave the desired products in good yields.
Aryllithium compounds bearing alkoxycarbonyl groups: Generation and reactions using a microflow system
Nagaki, Aiichiro,Kim, Heejin,Yoshida, Jun-Ichi
supporting information; experimental part, p. 7833 - 7836 (2009/04/10)
Go with the flow: An effective method for the generation and reaction of aryllithium compounds bearing an alkoxycarbonyl group is developed using microflow systems with very short residence times together with fast mixing and efficient temperature control. A wide range of alkoxycarbonyl groups including ethoxycarbonyl and methoxycarbonyl groups are tolerant of the microflow conditions. (Chemical Equation Presented)
Diels-Alder reactions of 1,3-cyclohexadienes and 3-(trimethylsilyl)propynoates. A new synthesis of ortho-(trimethylsilyl)benzoate esters
Kleschick, William A.,Thornburgh, Scott
, p. 1793 - 1799 (2007/10/03)
Diels-Alder reaction of 1,3-cyclohexadienes and 3-(trimethylsilyl)propynoates yields ortho-(trimethylsilyl)benzoates.
Mechanism of Base-Catalyzed Desilylations of Aryl- and Heteroaryltrimethylsilanes
Effenberger, Franz,Spiegler, Wolfgang
, p. 3872 - 3899 (2007/10/02)
The influence of different bases on the cleavage of silicium-carbon bonds in aryl- and heteroaryltrimethylsilanes is investigated in the presence of benzaldehyde as electrophilic scavenger for the aryl and heteroaryl anions formed in this process.A reactivity gradation of the various basic catalysts employed is determined from the reactions with 2-(trimethylsilyl)benzothiazole (1).The increase of catalytic activity of the anions parallels that of their ion potential.Attack of the base at the Si atom is postulated as the first step in this reaction sequence, with subsequent dissociation of the pentacoordinated intermediate in the rate-determining step.The carbanion thus liberated rapidly reacts with benzaldehyde.In the differently substituted aryltrimethylsilanes 13, 13', and 13'' the dependency of aryl anion stability in the base-catalyzed carbodesilylation was investigated.The relative rates of reaction correlate with Hammett's ?-constants rather than with the corresponding aryl anion stabilities.
Silylated Biphenyl Derivatives, Ethyl Benzoates, and Benzophenones by Regioselective -Cycloadditions
Birkofer, Leonhard,Wahle, Bernd
, p. 3309 - 3315 (2007/10/02)
The cycloaddition of the N-methyl-2-pyridones 1a-d with phenyl(trimethylsilyl)ethyne (2) proceeds regioselectively to give silylated biphenyl derivatives 5a, 6b, 5c,d.Similarly the reactions of ethyl (trimethylsilyl)propiolate (3) and of benzoyl(trimethylsilyl)ethyne (4) with 1a-c afford the silylated ethyl benzoates 5e, 6f, 5g and the benzophenones 5h, 6i, 5j, respectively.
