Metal-dependant stereoselectivity in the Pauson-Khand cyclization of N-propargyl-γ-amino vinyl sulfones

Picó, Anna; Moyano, Albert

doi:10.3998/ark.5550190.0008.412

Cited by 3 publications

(1 citation statement)

References 13 publications

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“…In order to circumvent the high temperatures and long reaction times necessary to effect the PK cycloaddition, different promoters of the reaction have been widely applied, such as N-methylmorpholine N-oxide, 228 trimethylamine N-oxide, 229 phosphine oxides, 230 alkyl sulphides, 231 thioureas, 232,233 and hard Lewis bases, 234 and it has been found that the selectivity of the reaction depends both on the substrate structure and on the nature of the metal carbonyl/promoter. 235 The cyclization has been also performed as environmentally friendly green protocols, such as in dry-state adsorption conditions, 236 under microwave irradiation, 237,238 in ionic liquids, 239,240 in water, 241,242 and in supercritical ethylene. 243,244 The asymmetric approach to the Pauson-Khand reaction has been efficiently achieved, based on chiral auxiliarydirected π-face discrimination in acetylenic-cobalt carbonyl complexes.…”

Section: Pauson-khand Reactionmentioning

confidence: 99%

Synthesis of Cyclopentitols by Ring-Closing Approaches

2009

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Section: Pauson-khand Reactionmentioning

confidence: 99%

Synthesis of Cyclopentitols by Ring-Closing Approaches

2009

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Sulfur Dioxide: A Powerful Tool for the Stereoselective Construction ofCCBonds

Vogel

Marković

Turks

2013

Stereoselective Synthesis of Drugs and Natural Products

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For a long time, the use of sulfur dioxide in organic chemistry was limited to the synthesis of simple bulk materials such as sulfinate salts and sulfones. Conjugate bases of sulfones are carbon nucleophiles that can be used to construct CC single bonds and stereoselective CC double bonds. Sulfones can also be employed as electrophiles, for instance, in the stereo‐ and enantioselective α‐aminoalkylations of carbonyl compounds. α,β‐Unsaturated sulfones are excellent acceptors in asymmetric Michael additions. They are also good dienophiles. Sulfones and readily available sulfonyl chlorides are good electrophilic partners in desulfinylative CC cross‐coupling reactions catalyzed by transition metals, including iron. Sulfur dioxide undergoes reversible cheletropic additions with 1,3‐dienes and irreversible metallo‐ene reactions with allylmetals. Conditions have been found realizing the endergonic H‐ene reactions of SO 2 with alkenes. This permits the one‐pot synthesis of polyfunctional sulfinates, sulfones, and sulfonamides starting from alkenes. At a low temperature, the hetero‐Diels‐Alder additions of SO 2 generate unstable sultines that can be used as electrophiles in the stereoselective construction of CC bonds between electron‐rich alkenes and 1,3‐dienes. The reaction cascade permits the one‐pot construction of stereotriads and stereotetrads that can be used subsequently in two successive aldol reactions that give, in short ways (double chain elongation), long‐chain polyketide and polypropionate antibiotics.

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Formal Synthesis of Borrelidin: A Highly Enantio- and Diastereoselective Access to the Morken’s C2–C12 Intermediate

Gembus

Karmazin

Uguen

et al. 2018

Bulletin of the Chemical Society of Japan

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In contrast to methyl and isobutyl phenyl sulfone, condensing under basic conditions higher alkyl sulfones and trans-2,3-epoxy-butanol 13c (or its O-benzyl and O-silyl derivatives) proved unfeasible, a difficulty that was overcome by using mono ethers of trans-2,3-epoxy-butane-1,4-diol 35c as the electrophilic reagents. Thus, adding excess BuLi to a mixture of the benzyl ether 35b and sulfone ent-12a, a stereodiad sulfone prepared in pure state from the R-Roche ester, via the O-trityloxy-sulfone ent-12c (X-ray), gave, after elimination by column chromatography of the side-formed regioisomer, a diol-sulfone that was next converted to sulfone 20 by means of conventional functional-group modifications. Reacting likewise this sulfone with the parent O-PMB derivative 35a, and then proceeding to the same purification process and function adjustment, delivered the title fragment in virtually pure state.

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Metal-dependant stereoselectivity in the Pauson-Khand cyclization of N-propargyl-γ-amino vinyl sulfones

Abstract: An efficient enantioselective route to N-propargyl-γ-amino vinyl sulfones has been developed, and their Pauson-Khand cyclization has been investigated. The stereoselectivity of the reaction depends both on the structure of the substrate and on the nature of the metal-carbonyl promoter.

Cited by 3 publications

References 13 publications

Synthesis of Cyclopentitols by Ring-Closing Approaches

Synthesis of Cyclopentitols by Ring-Closing Approaches

Sulfur Dioxide: A Powerful Tool for the Stereoselective Construction ofCCBonds

Formal Synthesis of Borrelidin: A Highly Enantio- and Diastereoselective Access to the Morken’s C2–C12 Intermediate

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