β-Amino tertiary cycloalkanols for the enantioselective protonation of enolic species produced by a palladium-induced cascade reaction

Aboulhoda, S. J.; Reiners, I.; Wilken, J.; Hénin, Françoise; Martens, Jürgen; Мuzart, Jacques

doi:10.1016/s0957-4166(98)00189-x

Cited by 32 publications

(17 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At room temperature under these conditions, KE* afforded 2-methylindanone in high yield but without optical activity (Scheme 5). This result highly contrasts with the formation, under similar conditions, of K* from the hydrogenolysis of KE in the presence of AH* (Scheme 1), 8,9,18,19 and agrees with an enantioselection depending on the asymmetric protonation of the ammonium enolate (Scheme 3, path b). As the enantioselectivity obtained from KE using the Pd/AH* procedure depends on the experimental conditions, 8,9,18,19 we have however to remember that competitive pathways, such as the reductive elimination of Pd 0 from hydridopalladium enolate Pd E and the tautomerisation of enol E, 7,18 can also lead to K (Scheme 6).…”

Section: Methodsmentioning

confidence: 48%

“…As unichiral β-aminoalcohols having a secondary amino group were used for the synthesis of K* from KE, 8,9,18 the Pd-catalyzed hydrogenolysis of KE* was carried out with 2-(methylamino)ethanol as the protonating species. At room temperature under these conditions, KE* afforded 2-methylindanone in high yield but without optical activity (Scheme 5).…”

Section: Methodsmentioning

confidence: 99%

“…[1][2][3][4][5][6] Over the past years, we contributed to this topic using various substrates and procedures. 7 With 2-methyl-2-benzyloxycarbonyl-1-indanone (KE) as the substrate, the procedure, studied in collaboration with Martens team, 8,9 involves a Pd-catalyzed hydrogenolysis in the presence of an unichiral 10 β-aminoalcohol (AH*) (Scheme 1). In the present paper, we discuss the nature of the intermediate responsible of the enantioselection, and the result of the reaction occurring with optically active 2-methyl-2-benzyloxycarbonyl-1-indanone and an achiral β-aminoalcohol (AH).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

On the mechanism of the domino reaction of 2-methyl-2-benzyloxycarbonyl-1-indanone mediated by palladium, hydrogen and aminoalcohols

Müller¹,

Hénin²,

Мuzart³

2014

Arkivoc

View full text Add to dashboard Cite

Whereas the Pd-catalyzed hydrogenolysis of racemic 2-methyl-2-benzyloxycarbonyl-1-indanone in the presence of an unichiral (enantiopure) aminoalcohol leads to optically active 2-methylindanone, such a domino reaction using optically active 2-methyl-2-benzyloxycarbonyl-1-indanone and an achiral aminoalcohol affords racemic 2-methylindanone. According to these results, the ketone is obtained from the aminoalcohol-mediated protonation of an enolic species.

show abstract

Section: Methodsmentioning

confidence: 48%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

On the mechanism of the domino reaction of 2-methyl-2-benzyloxycarbonyl-1-indanone mediated by palladium, hydrogen and aminoalcohols

Müller¹,

Hénin²,

Мuzart³

2014

Arkivoc

View full text Add to dashboard Cite

show abstract

“…[85][86][87] In the early reports, 2-methyl-1-indanone (3) and 2-methyl-1-tetralone (4) were obtained in up to 52% and 50% enantiomeric excesses (ee) from the corresponding β-keto esters 1 or 2, 86 whereas the benzyl carbonate 5 gave the optically enriched ketone 4 in 64% ee. 87 Several chiral diamines and amino alcohols were tested, 88,89 and the best results were obtained with (+)-endo-2-hydroxy-endo-3-aminobornane (Scheme 1, CA2*). Optimization of the reaction conditions using this chiral amine afforded 3 in up to 99% ee in the cascade reaction of 1.…”

Section: Heterogeneous Catalytic One-pot Reactions Including Homogenementioning

confidence: 99%

“…3. [88][89][90][91][92][93][94][95] In most of these reactions, high yields were reached accompanied by good ees (70 ± 5%). Prominent ee was reported only in the reaction of 1.…”

mentioning

confidence: 94%

Asymmetric one-pot reactions using heterogeneous chemical catalysis: recent steps towards sustainable processes

Szőllősi

2018

Catal. Sci. Technol.

View full text Add to dashboard Cite

The preparation of optically pure fine chemicals is among the most important and challenging tasks met by organic chemists. Recently, significant efforts have been focused on the development of green and sustainable procedures for the synthesis of these high value-added compounds. Asymmetric heterogeneous catalysis has provided efficient solutions to these challenges. The application of heterogeneous chiral catalysts in one-pot processes combines the advantages of use of these materials with time, material, and energy savings associated with cascade or sequential procedures. This review surveys these asymmetric onepot reactions reported until July 2017, in which a heterogeneous chemical catalyst has been applied either as a single multifunctional catalyst or in combination with a second catalytically active material. These processes include one-pot procedures catalysed by carefully designed solids obtained by the immobilization of chiral metal complexes, by anchoring chiral organocatalysts, or by modifying catalytic surfaces with optically pure compounds, which may also incorporate uncatalyzed and homogeneously catalysed steps. Methods applying achiral heterogeneous catalysts in combination with soluble chiral chemical catalysts or biocatalysts are also presented. Sophisticated, finely tuned materials have been applied in most of these reactions, which have been discussed along with the main requirements necessary to perform these transformations in a one-pot manner.

show abstract

Recent Developments in Enantioselective Deprotonation Mediated by Sub-Stoichiometric Quantities of Chiral Bases

Eames

2002

Eur. J. Org. Chem.

View full text Add to dashboard Cite

Recent developments in the enantioselective deprotonation of prostereogenic substrates by use of substoichiometric quantities of chiral bases are discussed. The effect that reac-The enantioselective deprotonation of prochiral substrates is very well documented. [1] This reaction has been shown to be diverse, and has resulted in the development of efficient methodologies for the synthesis of a wide range of optically active substrates, such as allylic alcohol 1, [2a] substituted silane 2 [2b] and vinyl bromide 3 [2c] (Scheme 1). The majority of reports have dealt with the use of a stoichiometric amount of a chiral base. [1,2] Despite the potential, [3] there are still very few examples of analogous substoichiometrically mediated processes. [4] The concept of substoichiometrically mediated deprotonation is still in its infancy, whereas the related substoichiometrically mediated chiral protonation of prostereogenic substrates is much more mature. [5Ϫ7] This related methodology relies on the initial formation of the corresponding conjugate base, usually an enolate, [5] by MeLi addition to a silyl enol ether, [8a] SmI 2 /allyl iodide addition to a ketene, [8b] or by simple deprotonation. [8c] Addition of a substoichiometric quantity of chiral acid HA* (typically 10 mol %) in the presence of a suitable stoichiometric quantity [a] 393 tion parameters (such as solvent, temperature and additive) have on the stereoselectivity are outlined.Scheme 1. Enantioselective deprotonation mediated by a stoichiometric quantity of chiral base of donor acid HA has resulted in the synthesis of optically active ketones 4 and 5 and amide 6 in good yield (Scheme 2). In many cases, the resulting stereocontrol has been shown to be superb and evidently illustrates the con-

show abstract

β-Amino tertiary cycloalkanols for the enantioselective protonation of enolic species produced by a palladium-induced cascade reaction

Cited by 32 publications

References 14 publications

On the mechanism of the domino reaction of 2-methyl-2-benzyloxycarbonyl-1-indanone mediated by palladium, hydrogen and aminoalcohols

On the mechanism of the domino reaction of 2-methyl-2-benzyloxycarbonyl-1-indanone mediated by palladium, hydrogen and aminoalcohols

Asymmetric one-pot reactions using heterogeneous chemical catalysis: recent steps towards sustainable processes

Recent Developments in Enantioselective Deprotonation Mediated by Sub-Stoichiometric Quantities of Chiral Bases

Contact Info

Product

Resources

About