Enolate formation from cyclopropyl ketones via iodide-induced ring opening and its use for stereoselective aldol reaction

Han, Zhenfu; Uehira, Shigeki; Tsuritani, Takayuki; Shinokubo, Hiroshi; Oshima, Koichiro

doi:10.1016/s0040-4020(00)01094-2

Cited by 72 publications

(38 citation statements)

References 21 publications

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“…The present computations were based on the cycloaddition reaction of (S)-1 with benzaldehyde catalyzed by Sn(OTf) 2 . All computations were carried out by using the Gaussian03 program package.…”

Section: Computational Methods and Modelsmentioning

confidence: 99%

“…By employing ligand control to effect absolute stereochemical induction, a series of stereoselective cycloaddition reactions were developed. [1][2][3][4][5] Recently, Pohlhaus et al described a highly diastereoselective synthesis of 2,5-disubstituted tetrahydrofurans (2) by Lewis acid catalyzed cycloaddition of donor-acceptor (D-A) cyclopropanes (1) and aldehydes (Scheme 1). Further, tetrahydrofuran 2 can undergo decarboxylation in a stereoselective manner to afford monoester 3 in good yield.…”

Section: Introductionmentioning

confidence: 99%

“…In Pohlhaus' experiment, [7] by utilizing Sn(OTf) 2 (OTf = trifluoromethane sulfonate) as a catalyst and CH 2 Cl 2 as a solvent, the cycloaddition reaction of D-A cyclopropanes [(S)-1] and benzaldehyde afforded tetrahydrofuran 2 in 96 % ee, 100 % conversion and Ͼ100:1 diastereomeric ratio. On the contrary, strong Lewis acids such as TiCl 4 and AlCl 3 give significant decomposition of the cyclopropane, whereas several milder Lewis acids such as SnCl 2 , ZnCl 2 , Mg-(OTf) 2 and La(OTf) 2 exhibit no reactivity towards the cyclopropane. Interestingly, their labelling study in which one of the diastereotopic carboxymethyl groups of the cyclopropane was deuterated, compound 4, and subjected to the normal reaction conditions revealed 94 % of the label to be cis to the phenyl groups in the tetrahydrofuran.…”

Section: Introductionmentioning

confidence: 99%

“…In addition, they suggested that the ligand control might not be necessary. Considering this significant method for the preparation of regiodefined tetrahydrofurans, it was necessary to arbitrate the cycloaddition reaction mechanism to account for the specific function of the Sn(OTf) 2 in the activation of the D-A cyclopropanes. Hence, the comprehensive theoretical investigation of the complete reaction cycle for the Sn(OTf) 2 -catalyzed synthesis of 2,5-disubstituted tetrahydrofuran from D-A cyclopropane and benzaldehyde was performed in the present work.…”

Section: Introductionmentioning

confidence: 99%

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DFT Study on the Sn^II‐Catalyzed Diastereoselective Synthesis of Tetrahydrofuran from D–A Cyclopropane and Benzaldehyde

Zhang¹,

Shen²,

Li³

2007

Eur J Org Chem

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By means of density functional theory (DFT), the regio‐ and diastereoselective mechanism for the synthesis of 2,5‐disubstituted tetrahydrofuran from a donor–acceptor (D–A) cyclopropane cycloaddition reaction with benzaldehyde catalyzed by Sn(OTf)2 was investigated. As demonstrated, the overall reaction includes the activation of the D–A cyclopropane (S)‐1, an unusual SN2 attack on the activated cyclopropane, the formation of the tetrahydrofuran coordination complex and the regeneration of the catalyst. The D–A cyclopropane is activated by its combination with Sn(OTf)2, which leads to a decrease in the natural bond orbital (NBO) energy ofσ*(C1–C2) and an increase in the dipole moment and angular deviation of the bent bond σ(C1–C2). Two nucleophilic reactions generates two chiral carbon centres, and the first one is rate controlling. In the SN2 reaction, one molecule of trifluoromethane sulfonate forms a hydrogen‐bond H(CHO)···O(OTf), which can control the stretching direction of the benzaldehyde. On the whole, the solvation energies of the species increase with increases in the molecular dipole moments, and the solvent effects increase the reaction barriers. The theoretically predicted dominant product is cis‐(2R,5R)‐tetrahydrofuran. So these can satisfactorily account for the experimental observations.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

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Section: Computational Methods and Modelsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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DFT Study on the Sn^II‐Catalyzed Diastereoselective Synthesis of Tetrahydrofuran from D–A Cyclopropane and Benzaldehyde

Zhang¹,

Shen²,

Li³

2007

Eur J Org Chem

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“…Pioneering works of Reissig and co-workers in the eighties have already shown the potential of oxygen substituted cyclopropanes to access either tetrahydrofurans or lactones (Scheme 7.3, A and B). [10][11][12][13][14][15] Oshima and co-workers later showed that that unsubstituted cyclopropanes could also be used for the cycloaddition (Scheme 7.3, C), [16] and Yadav introduced in 2006 silyl activated cyclopropanes as another alternative (Scheme 7.3, D). [17] In 2011, Dobbs and co-workers demonstrated that cycloaddition of silylmethyl substituted cyclopropanes was also possible in the absence of the diester activating group.…”

Section: C-o Bond Formationmentioning

confidence: 99%

Synthesis of Saturated Heterocycles via Metal-Catalyzed Formal Cycloaddition Reactions That Generate a C–N or C–O Bond

Waser

2013

Topics in Heterocyclic Chemistry

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In this section, the synthesis of saturated N-and O-heterocycles via formal cycloaddition is presented. The main focus is on metal-catalyzed reactions involving C-C or C-X  bond cleavage in three-or four-membered rings. After a fast presentation of pioneering works, the important breakthroughs of the last two decades are presented. The section starts with reactions involving three-membered rings. Formal [3+2] cycloadditions of donor-acceptor-substituted cyclopropanes and methylenecyclopropanes with carbonyls and imines are important methods to access tetrahydrofuran and pyrrolidine heterocycles. Formal [3+3] cycloadditions have emerged more recently. On the other hand, reactions of epoxides and aziridines with carbon monoxide or cumulenes are now well-established method to access heterocycles. These processes have been completed more recently with cycloaddition with olefins, carbonyls and imines. The section ends with the emerging field of four-membered ring activation for cycloaddition with  systems. This is the peer reviewed version of the following article: Top. Heterocycl. Chem. 2013, 32, 225, which The discovery of classical cycloaddition reactions, such as the (hetero) DielsAlder and 1,3-dipolar cycloadditions, has contributed tremendously to a more efficient access towards both carbocycles and heterocycles. The introduction of the term cycloaddition was necessary to distinguish these new types of reactions from previously discovered processes leading to cyclic structures, such as the famous Robinson annulation. In principle, each cycloaddition can be considered as a special case of the more general annulation process, but from which point on an annulation can be called a cycloaddition has been the topic of intensive discussions for decades, and is still not settled today. In 1968, Huisgen proposed a set of rules for the definition of cycloaddition, and the two first are still largely recognized as prerequisite: Although the rule that all the atoms of the starting materials have to be included in the product is not explicitly included in the definition, this requirement is usually recognized by most organic chemists. Even if electrocyclic cyclization processes were included in the original definition of Huisgen, the term cycloaddition is mostly used today for those reactions proceeding via the formation of at least two new bonds. Nevertheless, several researchers think that the term cycloaddition should be more strictly limited to reactions involving a continuous overlap of  electrons, and consequently allowing a concerted process. In fact, in his seminal publication, Huisgen already introduced further rules, in particular rule number 3, which explicitly stated that cycloadditions should not involve the cleavage of sigma bonds: -Huisgen Rule 3: "Cycloadditions do not involve the cleavage of  bonds." Unfortunately, in the same publication, Huisgen also described several reactions proceeding via -bond cleavage as cycloaddition. To solve this definition dilemma, several researchers have used th...

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Methanesulfonamide

Soundararajan¹,

Jacobs²

2007

Encyclopedia of Reagents for Organic Synthesis

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Enolate formation from cyclopropyl ketones via iodide-induced ring opening and its use for stereoselective aldol reaction

Cited by 72 publications

References 21 publications

DFT Study on the Sn^II‐Catalyzed Diastereoselective Synthesis of Tetrahydrofuran from D–A Cyclopropane and Benzaldehyde

DFT Study on the Sn^II‐Catalyzed Diastereoselective Synthesis of Tetrahydrofuran from D–A Cyclopropane and Benzaldehyde

Synthesis of Saturated Heterocycles via Metal-Catalyzed Formal Cycloaddition Reactions That Generate a C–N or C–O Bond

Methanesulfonamide

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Enolate formation from cyclopropyl ketones via iodide-induced ring opening and its use for stereoselective aldol reaction

Cited by 72 publications

References 21 publications

DFT Study on the SnII‐Catalyzed Diastereoselective Synthesis of Tetrahydrofuran from D–A Cyclopropane and Benzaldehyde

DFT Study on the SnII‐Catalyzed Diastereoselective Synthesis of Tetrahydrofuran from D–A Cyclopropane and Benzaldehyde

Synthesis of Saturated Heterocycles via Metal-Catalyzed Formal Cycloaddition Reactions That Generate a C–N or C–O Bond

Methanesulfonamide

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Product

Resources

About

DFT Study on the Sn^II‐Catalyzed Diastereoselective Synthesis of Tetrahydrofuran from D–A Cyclopropane and Benzaldehyde

DFT Study on the Sn^II‐Catalyzed Diastereoselective Synthesis of Tetrahydrofuran from D–A Cyclopropane and Benzaldehyde