Efficient optimization procedures in chiral catalysis are usually linked to a straightforward strategy to access groups of structurally similar catalysts required for fine-tuning. The ease of building up such ligand libraries can be increased when the structure-modifying step (introduction of a substituent) is done at a later stage of the synthesis. This is demonstrated for the extended family ...

Radical-radical cross coupling reactions of photoexcited 9-fluorenones have been accomplished for the first time, leading to the synthesis of 9-alkyl, pyrollidinyl and spiro-THF derivatives of 9-fluorenones. The method also reveals, for the first time, the behaviour of ketyl radicals in decarboxyaltive alkylation and ring expansion reactions.

Association of enantiopure TRISPHAT anion (1) with chiral spiro [Cu(LL')2] complexes (LL' = 2-R-phen, 2, 6-R-bpy, 3, and 2-iminopyridine, 4) leads to an efficient NMR enantiodifferentiation. Variable temperature 1H NMR spectroscopy has been used to determine the isomerisation kinetics of these pseudo-tetrahedral complexes and to evaluate their configurational stability; the latter depending on ...

(-)-(4S, 8S)-Foedanolide (1a) and (+)-(4R, 8R)-foedanolide (1b), a pair of new spiro-γ-lactone enantiomers, were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis foedan by HPLC using a chiral column, achieving over 7% ee. Their structures and absolute configurations were determined on the basis of extensive analysis of NMR spectra combined with computational me...

accumulating evidence indicates that aldosterone plays a critical role in the mediation of oxidative stress and vascular damage. nadph oxidase has been recognized as a major source of oxidative stress in vasculature. however, the relation between nadph oxidase in aldosterone-mediated oxidative stress in endothelial cells remains to be ascertained. the present study aimed to investigate the rele...

Heterocyclic compounds containing β-lactum structure with different hetero atoms are found to show biological activities1. In the present work, it has been synthesized the semicarbozone and thiosemicarbozone derivatives of 3-methyl-2,6-diphenylpiperidin-4-one followed bycyclisation to get the spiro compounds. These spiro compounds. The spiro products have been characterized by C,H,M analysis, I...

the development of multicomponent reactions (mcrs) designed to produce elaborate biologically active compounds has become an important area of research in organic, combinatorial, and medicinal chemistry. a comparative study of the synthesis of new bis-spiro-oxindolo(pyrrolizidines/pyrrolidines) ring systems by the cycloaddition of azomethine ylides generated by a decarboxylative route from sarc...

We propose a spectrum-dependent mechanism for the oxidation of 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (Spiro-OMeTAD) with bis(trifluoromethane)sulfonimide lithium salt (LiTFSI), which is commonly used in perovskite solar cells as the hole transport layer. The perovskite layer plays different roles in the Spiro-OMeTAD oxidization for various spectral ranges. The eff...