Individual (^f,tA)‐ and (^f,tC)‐Fullerene‐Based Nickel(II) Glycinates: Protected Chiral Amino Acids Directly Linked to a Chiral π‐Electron System

Abstract

Stereoselective electrosynthesis of the first individual ( f,t A)-and ( f,t C)-1,4-fullerene derivatives with anon-inherently chiral functionalization pattern is described, as well as the first example of an optically pure protected primary amino acid directly linked to the fullerene through only the chiral a-aminoacid carbon atom. An application of an auxiliary chiral nickel-Schiff base moiety as derivatizing agent allowed separation of ( f,t A)-and ( f,t C)-1,4-fullerene derivatives using an achiral stationary phase,aseparation whichh as never been done before.Scheme 1. Synthesis of complexes 1 and 2.

Separation of enantiomers of chiral fullerene derivatives through enantioselective encapsulation within an adaptable helical cavity of syndiotactic poly(methyl methacrylate) with helicity memory

“…Chiral fullerenes have attracted considerable attention due to their unique chiral nanocage structures and promising applications in materials science, biology, and medicine 1–11 . In the past two decades, the chirality of fullerenes has played a key role in the formation of photoconductive nanofibers by supramolecular self‐assembly 12 and the detection of circularly polarized light in organic field‐effect transistors 13 as well as in the formation of one‐handed helical poly(phenylacetylene)s 14,15 .…”

Reductive opening of a cyclopropane ring in the Ni(II) coordination environment: a route to functionalized dehydroalanine and cysteine derivatives

“…Recently, we elaborated a versatile electrochemical approach for the stereoselective functionalization of a side chain of amino acids involved in the Ni(II) chiral coordination environment [9][10][11][12][13][14][15]. A combination of redox-activity and chirality provided by the Ni-Schiff base template, supported with the protection from redox-destruction of the amino acid skeleton, makes the suggested approach a convenient route to various types of nonproteinogenic amino acids [9,10,12,13]. Recently, several practical approaches to α,α-cyclopropanated amino acids in the form of Ni(II)-Schiff base complexes were suggested [16][17][18][19], including electrochemical ones [15].…”