Metal-Free β-Amino Alcohol Synthesis: A Two-step Smiles Rearrangement

TMSCN-Promoted Difunctionalization of Alkenes for the Synthesis of Alcohol Derivatives

A TMSCN-promoted difunctionalization of styrenes with CHCl3 and TBHP is reported via the radical addition/cross coupling process. A wide range of dichloromethyl-substituted alcohol derivatives were synthesized under transition-metal-free conditions. Besides, this method is also applicable to unactive alkenes. The key to this success lies in the role of TMSCN, which prevents the reaction toward dichloromethylperoxylation of olefins. This represents an alternative approach for synthesizing diverse alcohol derivatives using readily available substrates, holding significant promise in the fields of pharmaceutical chemistry and natural product synthesis.

SO2-Extrusive 1,4-(Het)Aryl Migration: Synthesis of α-Aryl Amides and Related Reactions

(Het)aryl migration has emerged as a key synthetic tool and has particularly been exploited for the synthesis of α-aryl amides. This method overcomes the existing α-arylation methods, which are not always compatible with the introduction of (het)aryl groups possessing bulky or electrophilic substituents. This review focuses on SO2-extrusive (het)aryl migration in the frame of α-aryl amide synthesis. Anion- and radical-mediated transformations are reported, including the synthesis of polycyclic compounds through cascade reactions.

1 Introduction

2 Anionic Aryl Migration

3 Radical Aryl Migration

4 Conclusion

Brønsted Acid-Catalysed Epoxide Ring-Opening Using Amine Nucleophiles: A facile access to β-amino alcohols

A mild, efficient, and metal-free synthetic protocol for the synthesis of β-amino alcohols is reported. The reaction proceeds at room temperature with only 0.5 mol% catalyst loading and affords β-amino alcohol derivatives in excellent yield. This protocol is well-tolerated by a wide range of styrene oxide and aniline derivatives. A notably efficacious gram-scale synthesis is also reported with a high TON = 842. Further, the Hammett correlation study was also performed to identify the rate-determining step.

Diarylamine Synthesis via Desulfinylative Smiles Rearrangement

Diarylamines are obtained directly from sulfinamides through a novel rearrangement sequence. The transformation is transition metal-free and proceeds under mild conditions, providing facile access to highly sterically hindered diarylamines that are otherwise inaccessible by traditional S_NAr chemistry. The reaction highlights the distinct reactivity of the sulfinamide group in Smiles rearrangements versus that of the more common sulfonamides.

Transition Metal-Free, Methoxide-Catalyzed Synthesis of Pyridoindolones

A simple transition metal-free strategy for the synthesis of pyrido[1,2-a]indolone derivatives has been devised through sodium methoxide-catalyzed intramolecular cyclization of 2-alkenylated N-pyrimidyl indoles. The reactions involved a Smiles rearrangement/cyclization cascade, which resulted in a new series of N-fused indoles, potentially applicable skeletons in medicinal chemistry. This reaction presents simple eco-friendly reaction conditions, a high atom- and cost-economy, a short reaction time, and a broad range of substrate scope with high reaction efficiency.