Synthesis of heterocycles by cyclization of unsaturated organolithiums: a review

Mealy, Michael J.; Bailey, William F.

doi:10.1016/s0022-328x(01)01244-x

Cited by 91 publications

(34 citation statements)

References 57 publications

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“…4 The intramolecular carbolithiation of carbon-carbon double bonds is an interesting procedure to prepare functionalized carbocyclic and heterocyclic compounds. 5 Thus, the carbanionic cyclization reaction of different alk-5-enyllithium intermediates has been extensively studied. 6-8 Bailey et al reported a very interesting methodology employing a catalytic amount of phenyllithium that allowed the cycloisomerization of different alkenyl primary, secondary, tertiary, and aryl iodides to the corresponding cyclic isomer iodides, and the mechanism of this procedure being substrate dependent.…”

Section: Introductionmentioning

confidence: 99%

Cyclopropylmethyl- and cyclobutylmethyllithium by an arene-catalyzed lithiation. Stability and reactivity

2010

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Section: Introductionmentioning

confidence: 99%

Cyclopropylmethyl- and cyclobutylmethyllithium by an arene-catalyzed lithiation. Stability and reactivity

2010

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“…[3] Let us first discuss the case of alkyne 1. Intramolecular carbolithiations of triple bonds that are associated with beliminations have been observed in other situations.…”

Section: Introductionmentioning

confidence: 99%

A Case of anti Carbolithiation of Alkynes Resulting from Intramolecular Lithium Coordination

Fressigné

Girard

Durandetti

et al. 2008

Chemistry A European J

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The mechanism of the intramolecular carbolithiation of lithiated propargylic ether 2 has been investigated both experimentally and theoretically. The results show that the action of one equivalent of n-butyllithium on 1 is sufficient to trigger halogen-lithium exchange and the subsequent heterocyclization step. Interestingly, the reaction stops at the stage of dihydrobenzofuran 6; no spontaneous elimination of lithium ethylate was observed. The fact that the E configuration of this adduct was exclusively produced suggests that the reaction proceeds by following an unprecedented anti addition on the alkyne. According to DFT calculations, this unexpected outcome is related to the intramolecular coordination of the lithium by one oxygen atom of the terminal acetal appendage: the O-Li interaction, which persists all along the ring-closure process, drives the cation to the E site of the final olefin. The calculations also show that in the absence of this coordination (as in conformers B and C of acetal 2), the Z olefin that results from a classical syn addition of the aryllithium should be obtained. The experiments were repeated with allene 1d. In this case, one equivalent of n-butyllithium suffices to trigger not only the exchange and the cyclization, but also the final elimination of lithium ethoxide. The DFT results indicate that the intramolecular addition of the original aryllithium on the central carbon atom of the allene 2b yields the expected benzofuran skeleton 3b, which bears a lithiated lateral chain at the 3-position. Both cyclizations go through low-lying transition states, as is expected for rapid reactions at low temperature.

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“…The best enantioselectivities were achieved with aryllithiums containing ortho-substituents and employing (-)-sparteine. The intramolecular carbolithiation of carbon-carbon double bonds is an interesting route to generate functionalised carbocyclic and heterocyclic compounds [75]. Indeed, the carbanion cyclisation reaction of 5-alkenyllithiums, such as 115, to the corresponding cyclopentylmethyllithium derivatives was investigated [76], along with their further electrophilic substitution employing mainly carbonylic compounds as electrophiles [77].…”

Section: Addition To Carbon-carbon Double Bondsmentioning

confidence: 99%

Non-Deprotonating Methodologies for Organolithium Reagents Starting from Non-Halogenated Materials. Part 2: Transmetallation and Addition to Multiple Bonds

Guijarro¹,

Pastor²,

Yus

2011

COC

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The recent publications on the topic of the preparation of organolithium reagents by non-deprotonating methodologies and starting from non-halogenated substrates have been covered in the present revision. In this second part, transmetallation processes, mainly tin-lithium exchange, and addition to multiple bonds have been considered. Moreover, other procedures, such as carbon-carbon bond scission and the Shapiro reaction, have been included.

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Synthesis of heterocycles by cyclization of unsaturated organolithiums: a review

Cited by 91 publications

References 57 publications

Cyclopropylmethyl- and cyclobutylmethyllithium by an arene-catalyzed lithiation. Stability and reactivity

Cyclopropylmethyl- and cyclobutylmethyllithium by an arene-catalyzed lithiation. Stability and reactivity

A Case of anti Carbolithiation of Alkynes Resulting from Intramolecular Lithium Coordination

Non-Deprotonating Methodologies for Organolithium Reagents Starting from Non-Halogenated Materials. Part 2: Transmetallation and Addition to Multiple Bonds

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