Photoredox-Catalyzed Synthesis of β-Amino Alcohols: Hydroxymethylation of Imines with α-Silyl Ether as Hydroxymethyl Radical Precursor

Abstract

Carbon−carbon bond formation is an efficient approach for the synthesis of amino alcohols using two simple starting materials. Herein, we present a novel method for a divergent synthesis of β-amino ethers and β-amino alcohols in a sequential one-pot protocol under high-efficiency, mild, and metalor metal-free conditions. Especially, TMSCH 2 OPMP was developed as a synthetic equivalent of α-hydroxymethyl radical in an in situ photocatalyzed oxidative PMP group deprotection strategy under air. A preliminary mechanistic investigation provides evidence for reaction mechanism involving a photoinduced α-alkoxy methyl radical and superoxide.

Photoinduced Formal [4+2] Cycloaddition of Two Electron-deficient Olefins: Synthesis of Lucidumone

“…In the case where chemoselectivity is an issue, the [4+2] cycloaddition occurred predominantly at the enone motif (10), leaving the phenylacetylene functionality intact. The reaction was also found to be compatible with several sensitive groups, such as phenol ester (12) that could be easily hydrolyzed, and α-TMS-substituted ethers (13) that fragment with cleavage of the silyl group via photoinduced electron transfer (PET) [30][31][32][33] . Removal of the methyl enol ether functionality of the enone substrate resulted in a dramatic decline of reaction e ciency, affording 14 in 57% yield.…”

Arylation of Diethyl Acetamidomalonate with Diaryliodonium Salts En Route to α-Arylglycines

“…For this reason, they are widely used as valuable building blocks in drug discovery. Moreover, α-arylglycines serve as general precursors to β-amino alcohols, important intermediates in synthetic chemistry and ligands …”

Visible light-mediated three-component functionalization of olefins with sulfoxyimidoylsulfonium salt for the synthesis of β-amino alcohols and amino ethers

“…29 Visible light catalyzed synthesis of amino alcohols has made some progress in recent years. [30][31][32][33][34] In 2015, Akita reported a method for the simple and region-specific aminohydroxylation of olefins via photoredox catalysis using aminopyridine salts as amine sources. 30 In 2022, Zhang reported the use of urushiol derivatives as biomass-based photocatalysts for the synthesis of β-amino alcohols.…”