Organocatalytic synthesis of axially chiral tetrasubstituted allenes

Organic & Biomolecular Chemistry, Journal Year: 2022, Volume and Issue: 21(2), P. 252 - 272

Published: Dec. 5, 2022

Four organocatalytic approaches for the synthesis of axially chiral tetrasubstituted allenes are described with new critical insights into reaction scope and mechanisms.

Language: Английский

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Organocatalytic regio- and enantioselective C1-arylation of β,γ-alkynyl-α-imino esters with pyrrolo[2,1-a]isoquinolines

Chemical Communications, Journal Year: 2023, Volume and Issue: 60(7), P. 831 - 834

Published: Dec. 15, 2023

We herein report regio- and enantioselective arylation of β,γ-alkynyl-α-imino esters with pyrroloisoquinolines. Using chiral phosphoric acid catalysts, a wide range novel axially tetrasubstituted α-amino allenoates were accessed in good yields excellent enantioselectivities. Notably, this transformation occurred preferentially at the sterically more hindered C1-position The potential scalability late-stage functionalization demonstrated utility current protocol.

Language: Английский

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Organocatalytic enantio- and diastereoselective synthesis of trifluoro-ethylamine allenoate derivatives containing axial and central chiralities

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(79), P. 11116 - 11119

Published: Jan. 1, 2024

Herein, we report an example of a stereoselective γ-addition reaction trifluoromethyl ketimines to 1-alkynyl ketones mediated by isothiourea, BTM, under mild conditions, which afforded tetrasubstituted allenes with central chiralities in high yields (up 94% yield), good enantioselectivities 91% ee), and excellent diastereoselectivities (all >20 : 1 dr). In addition, the BTM-catalyzed was successfully applied gram-scale reaction, unexpected benzopyrrolothiazine derivative converted, albeit racemic.

Language: Английский

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Organocatalytic Asymmetric Dearomatization Reaction for the Construction of Axially Chiral Urazole Embedded Naphthalenones

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(8), P. 1185 - 1190

Published: March 29, 2023

Abstract Herein we disclose a catalytic asymmetric dearomatization reaction of β‐ naphthols with 4‐aryl‐1,2,4‐triazole‐3,5‐diones. A chiral phosphoric acid spiro motif was found to be effective for this reaction. The urazole embedded naphthalenones having both axial and central chirality were obtained in good high yields (70–85%) diastereo‐ enantioselectivities (>20:1, 8–96% ees), C−N rotational energy barrier 31.54 K.Cal.mol −1 t 1/2 25 °C=589.8 years. scope the broad few applications including bromo‐amination have been demonstrated. magnified image

Language: Английский

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Novel Stereo‐Induction Pattern in Pudovik Addition/Phospha‐Brook Rearrangement Towards Chiral Trisubstituted Allenes

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(22)

Published: March 23, 2024

Abstract Despite the significance of chiral allene skeletons in catalysis, organic synthesis and medicinal chemistry et al., there is a scarcity reports on axially allenyl phosphorus compounds. Here, we disclosed an efficient straightforward cascade reaction between ethynyl ketones phosphine oxides, resulting broad array trisubstituted allenes incorporating moiety high yields with excellent stereoselectivities facilitated by peptide‐mimic phosphonium salt (PPS) Additionally, comprehensive series mechanistic experiments have been conducted to elucidate that this proceeds via asymmetric Pudovik addition followed subsequent phospha ‐Brook rearrangement occurs concomitantly kinetic resolution, representing stereospecific protonation process facilitating central‐to‐axial chirality transfer manner. We anticipate our research will pave way for promising exploration novel stereo‐induction pattern addition/ reaction.

Language: Английский

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