we report an efficient protocol for the C(sp2)–H carbonylation of amino acid derivatives based on an inexpensive cobalt(II) salt catalyst. Carbonylation was accomplished using picolinamide as a tracelessdirectinggroup, CO (1 atm) as the carbonyl source, and Co(dpm)2 as the catalyst. A broad range of phenylalanine derivatives bearing diverse functional groups were tolerated. Moreover, the method can
Radical C−H Alkylation with Ethers and Unactivated Cycloalkanes toward the Assembly of Tetrasubstituted Amino Acid Derivatives
作者:Marcos San Segundo、Arkaitz Correa
DOI:10.1002/adsc.202200716
日期:2022.9.20
A radical α−C−H alkylation of a collection of N-picolinamide aminoacidderivatives with ethers and cycloalkanes as chemical feedstock is described. This cross-dehydrogenative coupling is distinguished by its reliable scalability and removable auxiliary group, and enables the assembly of a variety of tri- and tetrasubstituted aminoacid compounds.
straightforward approach for site-selective functionalization of phenylalanine and phenylalanine-containing peptide via a Pd-catalyzed tandem reaction has been developed. The robust method underwent dualC–Hactivation, including C–C coupling with benzoquinone and intramolecular C–N cyclization, providing a feasible and rapid synthetic route to incorporate 4-benzoquinone-indoline fragments into peptides.
Pd‐Catalyzed Arylation and Benzylation of Tyrosine at the <i>δ</i>−C(sp<sup>2</sup>)−H and C(2) Positions: Expanding the Library of Unnatural Tyrosines
作者:Prabhakar Singh、Srinivasarao Arulananda Babu
DOI:10.1002/ejoc.202300440
日期:2023.8.14
The Pd(II)-catalyzed picolinamide-directed arylation and benzylation at the remote δ−C(sp2)−H and C(2) position of the aryl ring in tyrosines and the assembling of C(2) arylated and benzylated tyrosines are reported. Expansion of the substrate scope in site-selective remote δ−C(sp2)−H functionalization and synthesis of biaryl-, terphenyl- and diarylmethane-based unnatural tyrosines and peptides are
Pd-Catalyzed Picolinamide-Directed C(sp2)–H Sulfonylation of Amino Acids/Peptides with Sodium Sulfinates
作者:Raghunath Bag、Nagendra K. Sharma
DOI:10.1021/acs.joc.4c00988
日期:2024.7.19
a Pd-catalyzed picolinamide-directed site-selective C(sp2)–H sulfonylation of amino acids and peptides with sodium sulfinates in moderate to good yields. Sulfonylation of levodopa and dopamine drug molecules and late-stage directed peptide sulfonylation are studied for the first time. Broad substrate scope having various functionalities, late-stage drug modifications, and various post synthetic utilities