Advanced Functionalization of Glycine Derivatives

Glycine derivatives represent a fundamental class of α-amino acids whose modification enables the creation of non-proteinogenic amino acids, pharmaceuticals and functional materials. Advanced functionalisation strategies seek to transform the inert α-C(sp3)–H and N–H bonds of glycine scaffolds into C–C, C–N and C–O linkages with high precision. Recent advances employ transition-metal catalysis, photoredox and electrocatalytic processes as well as organocatalysis to achieve site-selectivity and broad substrate scope. These methods combine atom economy and operational simplicity, enabling late-stage diversification of peptide chains and small molecules. By harnessing radical mechanisms, directing groups and visible-light activation, chemists now access a diverse array of heterocycles, aromatic motifs and bioactive fragments. The refinement of these tools has global significance, facilitating rapid lead generation in drug discovery, agrochemical design and peptide-based materials.

Research from Nature Portfolio

A seminal development established a coordinating activation strategy for nickel-catalysed radical oxidative cross-coupling of α-amino acids with (hetero)arylmethyl radicals. This protocol achieves C(sp3)–H/C(sp3)–H bond union without pre-functionalisation, furnishing β-aromatic α-amino acids on gram scale. The method tolerates a wide variety of α-amino acid substrates and aromatic partners, employs an inexpensive metal catalyst and a removable directing group, and operates under mild conditions. Such an approach underscores the power of radical C–H activation to construct quaternary centres and complex amino acid libraries suitable for commercial synthesis.

Advanced Functionalization of Glycine Derivatives publication trend

The graph below shows the total number of articles in advanced functionalization of glycine derivatives across all publications each year (not limited to Nature Index journals).

Technical terms

C(sp3)–H activation: Functionalisation of a saturated carbon–hydrogen bond adjacent to an α-amino centre.

Cross-dehydrogenative coupling: Direct bond formation between two C–H bonds accompanied by hydrogen removal.

Photoredox catalysis: Use of light-activated catalysts to mediate oxidation and reduction steps.

Late-stage functionalisation: Introduction of new groups into complex molecules in final synthetic steps.

References

1. Coordinating activation strategy for C(sp3)–H/C(sp3)–H cross-coupling to access β-aromatic α-amino acids. Nature Communications (2015).
2. Photoredox Cross-Dehydrogenative Coupling of N‑Aryl Glycines Mediated by Mesoporous Graphitic Carbon Nitride: An Environmentally Friendly Approach to the Synthesis of Non-Proteinogenic α‑Amino Acids (NPAAs) Decorated with Indoles. The Journal of Organic Chemistry (2022).
3. Visible-Light-Driven α-C(sp3)–H Bond Functionalization of Glycine Derivatives. Catalysts (2023).
4. Oxidative Cross-Coupling of α‑Amino Ketones with Alcohols Enabled by I2‑Catalyzed C–H Hydroxylation. The Journal of Organic Chemistry (2023).