Synthesis of Enantioenriched γ-Amino-α,β-unsaturated Esters Utilizing Palladium-Catalyzed Rearrangement of Allylic Carbamates for Direct Application to Formal [3 + 2] Cycloaddition

Kondoh, Azusa; Kamata, Yuji; Terada, Masahiro

doi:10.1021/acs.orglett.7b00471

Cited by 18 publications

(9 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, we used insertion products 7n and 7t to synthesize bioactive compounds (Scheme C). Specifically, cannabinoid receptor 1 inhibitor 18 , which has a pyrrolidin-2-one core structure, was prepared from 7n by means of an allylic rearrangement–cyclization sequence (eqs e and f), demonstrating the potential utility of our protocol for the synthesis of important chiral pyrrolidin-2-ones . In addition, a formal synthesis of the chiral drug sertraline was realized by subjecting 7n to a palladium-catalyzed stereospecific allylic arylation (eq g) .…”

Section: Resultsmentioning

confidence: 96%

Highly Enantioselective O–H Bond Insertion Reaction of α-Alkyl- and α-Alkenyl-α-diazoacetates with Water

Zhao

Zhou

et al. 2020

J. Am. Chem. Soc.

View full text Add to dashboard Cite

Catalytic asymmetric reactions in which water is a substrate are rare. Enantioselective transition-metal-catalyzed insertion of carbenes into the O–H bond of water can be used to incorporate water into the stereogenic center, but the reported chiral catalysts give good results only when α-aryl-α-diazoesters are used as the carbene precursors. Herein we report the first highly enantioselective O–H bond insertion reactions between water and α-alkyl- and α-alkenyl-α-diazoesters as carbene precursors, with catalysis by a combination of achiral dirhodium complexes and chiral phosphoric acids or chiral phosphoramides. Participation of the phosphoric acids or phosphoramides in the carbene transfer reaction markedly suppressed competing side reactions, such as β-H migration, carbene dimerization, and olefin isomerization, and thus ensured good yields of the desired products. Fine-tuning of the ester moiety facilitated enantiocontrol of the proton transfer reactions of the enol intermediates and resulted in excellent enantioselectivity. This protocol represents an efficient new method for preparation of multifunctionalized chiral α-alkyl and α-alkenyl hydroxyl esters, which readily undergo various transformations and can thus be used for the synthesis of bioactive compounds. Mechanistic studies revealed that the phosphoric acids and phosphoramides promoted highly enantioselective [1,2]- and [1,3]-proton transfer reactions of the enol intermediates. Maximization of molecular orbital overlap in the transition states of the proton transfer reactions was the original driving force to involve the proton shuttle catalysts in this process.

show abstract

Section: Resultsmentioning

confidence: 96%

Highly Enantioselective O–H Bond Insertion Reaction of α-Alkyl- and α-Alkenyl-α-diazoacetates with Water

Zhao

Zhou

et al. 2020

J. Am. Chem. Soc.

View full text Add to dashboard Cite

show abstract

“…In the case of the palladium‐catalyzed transformation, the boron species is attempted to be essential for both the epoxide activation [41a] and the regioselectivity of the amine addition, as depicted in Scheme 5b. As an alternative, Terada recently established a palladium‐catalyzed decarboxylative rearrangement of enantioenriched allylic carbamates to prepare chiral γ‐amino‐α,β‐unsaturated esters (Scheme 5d) [41b] …”

Section: Chemical Route To Vinylogous and Heteroaromatic γ‐Amino Acidsmentioning

confidence: 99%

α,β‐Unsaturated γ‐Peptide Foldamers

Legrand

Maillard

2021

ChemPlusChem

View full text Add to dashboard Cite

Despite their concomitant emergence in the 1990s, γ-peptide foldamers have not developed as fast as β-peptide foldamers and to date, only a few γ-oligomer structures have been reported, and with sparse applications. Among these examples, sequences containing α,β-unsaturated γ-amino acids have recently drawn attention since the Z/E configurations of the double bond provide opposite planar restrictions leading to divergent conformational behaviors, from helix to extended structures. In this Review, we give a comprehensive overview of the developments of γ-peptide foldamers containing α,βunsaturated γ-amino acids with examples of applications for health and catalysis, as well as materials science.

show abstract

“…The aza-Michael strategy was also applied in the synthesis of enantioenriched β,γ-diamino acid derived imidazolidin-2-ones by Terada [179]. γ-Amino-α,β-unsaturated esters were caused to react with tosyl isocyanates in a formal [3 + 2] cycloaddition using 10% of DIPEA as the catalyst.…”

Section: Catalysts 2018 8 X For Peer Reviewmentioning

confidence: 99%

“…A similar approach was applied to the desymmetrization of cyclohexadienones with isocyanates in presence of a catalytic amount of DBU (1,8-Diazabicyclo(5.4.0)undec-7-ene) [179]. The authors reported the synthesis of a broad range of bicyclic imidazolidin-2-ones with high diastereomeric ratios (Scheme 63).…”

Section: Catalysts 2018 8 X For Peer Reviewmentioning

confidence: 99%

See 1 more Smart Citation

Recent Advances in the Catalytic Synthesis of Imidazolidin-2-ones and Benzimidazolidin-2-ones

et al. 2019

View full text Add to dashboard Cite

2-Imidazolidinone and its analogues are omnipresent structural motifs of pharmaceuticals, natural products, chiral auxiliaries, and intermediates in organic syntheses. Over the years, continuous efforts have been addressed to the development of sustainable and more efficient protocols for the synthesis of these heterocycles. This review gives a summary of the catalytic strategies to access imidazolidin-2-ones and benzimidazolidin-2-ones that have appeared in the literature from 2010 to 2018. Particularly important contributions beyond the timespan will be mentioned. The review is organized in four main chapters that identify the most common approaches to imidazolidin-2-one derivatives: (1) the direct incorporation of the carbonyl group into 1,2-diamines, (2) the diamination of olefins, (3) the intramolecular hydroamination of linear urea derivatives and (4) aziridine ring expansion. Methods not included in this classification will be addressed in the miscellaneous section.

show abstract

Synthesis of Enantioenriched γ-Amino-α,β-unsaturated Esters Utilizing Palladium-Catalyzed Rearrangement of Allylic Carbamates for Direct Application to Formal [3 + 2] Cycloaddition

Cited by 18 publications

References 27 publications

Highly Enantioselective O–H Bond Insertion Reaction of α-Alkyl- and α-Alkenyl-α-diazoacetates with Water

Highly Enantioselective O–H Bond Insertion Reaction of α-Alkyl- and α-Alkenyl-α-diazoacetates with Water

α,β‐Unsaturated γ‐Peptide Foldamers

Recent Advances in the Catalytic Synthesis of Imidazolidin-2-ones and Benzimidazolidin-2-ones

Contact Info

Product

Resources

About