Cross-Aldol Reaction of Activated Carbonyls with Nitrosocarbonyl Intermediates: Stereoselective Synthesis toward α‑Hydroxy-β-amino Esters and Amides

A practical and flexible strategy toward α-hydroxy-β-amino esters and amides, which are important biological motifs, based on an organocatalytic cross-aldol reaction of in situ-generated nitrosocarbonyl intermediates followed by hydrogenation is presented. The protocol features operational simplicity, high yields, a wide substrate scope, and high regio- and diastereoselectivity profiles. The utility of this method was showcased through the synthesis of bestatin analogues and indole formation

Advanced Nitroso Aldol Reaction: Metal-Free Cross-Coupling of Anilines with Silyl Enol Ethers en Route to α‑Amino Ketones

A practical and step-economical nitroso aldol reaction has been developed based on metal-free direct cross-coupling of ready-stock anilines with silyl enol ethers at room temperature affording α-amino ketones in high yields (up to 82%). The protocol features a one-pot cascade of nitroso compound generation, selective C–N bond formation, and N–O bond cleavage using solely inexpensive and user-friendly Oxone and displays remarkable functional group tolerance. The method was further extended to prepare densely functionalized indoles that are otherwise difficult to synthesize

Advanced Nitroso Aldol Reaction: Metal-Free Cross-Coupling of Anilines with Silyl Enol Ethers en Route to α‑Amino Ketones

A practical and step-economical nitroso aldol reaction has been developed based on metal-free direct cross-coupling of ready-stock anilines with silyl enol ethers at room temperature affording α-amino ketones in high yields (up to 82%). The protocol features a one-pot cascade of nitroso compound generation, selective C–N bond formation, and N–O bond cleavage using solely inexpensive and user-friendly Oxone and displays remarkable functional group tolerance. The method was further extended to prepare densely functionalized indoles that are otherwise difficult to synthesize

Cross-Aldol Reaction of Activated Carbonyls with Nitrosocarbonyl Intermediates: Stereoselective Synthesis toward α‑Hydroxy-β-amino Esters and Amides

A practical and flexible strategy toward α-hydroxy-β-amino esters and amides, which are important biological motifs, based on an organocatalytic cross-aldol reaction of in situ-generated nitrosocarbonyl intermediates followed by hydrogenation is presented. The protocol features operational simplicity, high yields, a wide substrate scope, and high regio- and diastereoselectivity profiles. The utility of this method was showcased through the synthesis of bestatin analogues and indole formation

Advanced Nitroso Aldol Reaction: Metal-Free Cross-Coupling of Anilines with Silyl Enol Ethers en Route to α‑Amino Ketones

A practical and step-economical nitroso aldol reaction has been developed based on metal-free direct cross-coupling of ready-stock anilines with silyl enol ethers at room temperature affording α-amino ketones in high yields (up to 82%). The protocol features a one-pot cascade of nitroso compound generation, selective C–N bond formation, and N–O bond cleavage using solely inexpensive and user-friendly Oxone and displays remarkable functional group tolerance. The method was further extended to prepare densely functionalized indoles that are otherwise difficult to synthesize

Synthesis of several types of 2,8-dioxabicyclo[3.3.1]nonanes using amberlyst-15 as an efficient recyclable heterogeneous catalyst

<p>A facile synthesis of 2,8-dioxabicyclo[3.3.1]nonane derivatives starting from simple molecules like 2-hydroxychalcones as one component and dimedone, 4-hydroxycoumarin, 2-hydroxynaphthoquinone, 2-naphthol or 1-naphthol, as the other has been achieved by use of amberlyst-15, a sulfonated polystyrene resin, as a recyclable heterogeneous catalyst. The methodology involves a domino sequence of Michael addition and two-stage cyclisation.</p

Advanced Nitroso Aldol Reaction: Metal-Free Cross-Coupling of Anilines with Silyl Enol Ethers en Route to α‑Amino Ketones

A practical and step-economical nitroso aldol reaction has been developed based on metal-free direct cross-coupling of ready-stock anilines with silyl enol ethers at room temperature affording α-amino ketones in high yields (up to 82%). The protocol features a one-pot cascade of nitroso compound generation, selective C–N bond formation, and N–O bond cleavage using solely inexpensive and user-friendly Oxone and displays remarkable functional group tolerance. The method was further extended to prepare densely functionalized indoles that are otherwise difficult to synthesize

Nitrosocarbonyl–Henry and Denitration Cascade: Synthesis of α‑Ketoamides and α‑Keto Oximes

An unprecedented Henry reaction of in situ generated nitrosocarbonyl intermediates and concomitant denitration cascade has been developed. The reaction is catalyzed by organic base at room temperature offering α-ketoamides, a demanding scaffold for drug discovery, in high yields. An alteration of substitution pattern also produced α-keto oximes, a high-value synthon. The protocol features operational simplicity and broad substrate scope