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Facile regiospecific intermolecular C–H insertion reactions of α-diazophosphonates with indole or pyrrole derivatives catalyzed by trifluoroborane have been developed. The reaction protocol was effective for regioselective C–H insertion depending on the substitution pattern on the indole moiety and carbene migratory model. This represents the first straightforward access to N-unsubstituted β-(3-indol)-β-aminophosphonates and β-(2-pyrrol)-β-aminophosphonates containing quaternary carbon centers in moderate to good yields.

Mercaptans and thiophenols participate in the insertion reaction with carbenoids generated in situ from α-diazophosphonates to produce N,S-acetals containing quaternary centers.

An iron-catalyzed asymmetric intramolecular cyclopropanation was realized in high yields and excellent enantioselectivity (up to 97 % ee) by using the iron complexes of chiral spiro-bisoxazoline ligands as catalysts. The superiority of iron catalysts exhibited in this reaction demonstrated the potential abilities of this sustainable metal in asymmetric carbenoid transformation reactions.

A series of dialkyl α-diazophosphonates bearing different substituents have been prepared from natural amino acids in order to investigate the steric effect in 1,2-migration reaction of metal carbenes. The diazo decomposition of the diazophosphonates using the AgOTf/NaBArF complex resulted in β-hydrogen migration to give β-amino (Z)-enylphosphonates in good yields with high regio- and stereoselectivity. A possible reaction mechanism shows that the steric effect could dramatically influence the geometric isomerism aptitude. This new method for constructing (Z)-β-amino vinylphosphonates should be of general utility in organic synthesis.

A palladium-catalyzed asymmetric O-H insertion reaction was developed. Palladium complexes with chiral spiro bisoxazoline ligands promoted the insertion of α-aryl-α-diazoacetates into the O-H bond of phenols with high yield and excellent enantioselectivity under mild reaction conditions. This palladium-catalyzed asymmetric O-H insertion reaction provided an efficient and highly enantioselective method for the preparation of synthetically useful optically active α-aryl-α-aryloxyacetates.

The Cu-catalyzed C—H functionalization/O—H insertion reaction of α-diazophosphonates (I) with alcohols (II) is developed.

The presented method is highly tolerable to functionalized N-phosphoryl imines and provides a reliable synthetic route to the corresponding β-nitro ethylphosphoramidates (III) with adjacent quaternary and tertiary chiral centers in high enantio- and diastereoselectivity.

Ferrocene compounds are a class of biologically active compounds that has antitumour and antifungal properties. This study investigated the induction of apoptosis in human fibrosarcoma cells (HT1080) after treatment with a series of 6-ferrocenyl-3-subsituted7H-1,2,4-triazolo[3,4-b]- 1,3,4-thiadiazine (FTFs). We found that FTFs could suppress the viability of HT1080 cells. Cell cycle analysis showed that proliferative inhibition of HT1080 cells occurred through apoptosis, as the cells were blocked in G1 phase. Moreover, mitochondrial membrane staining assay demonstrated that FTFs exposure significantly decreased mitochondrial membrane potential. Finally, under the stress of FTFs, Bax/Bcl-2 ratio in HT1080 cells was significantly increased. These results suggested that FTFs-induced apoptosis in HT1080 cells may work dependent on a Bax/Bcl-2 pathway.

A wide range of heterocyclic thiones or thiols are reacting with the aromatic and aliphatic iodides at the S-site exclusively to afford the thioethers with high yields.

A copper-catalyzed asymmetric intramolecular O-H insertion of ω-hydroxy-α-diazoesters has been accomplished by using chiral spiro bisoxazoline ligands. This highly enantioselective intramolecular O-H insertion reaction provides an efficient approach to a variety of synthetically important chiral 2-carboxy cyclic ethers with different ring sizes as well as substitution patterns.

Three chiral β-hydroxy amide ligands were prepared by the reaction of benzyl chloride with amino alcohols derived from l -tyrosine. The titanium(IV) complex of chiral ligand 4a was found to be an effective catalyst for the asymmetric addition of methyl propiolate to aliphatic and aromatic aldehydes. The γ-hydroxy-α,β-acetylenic esters were obtained in excellent enantiomeric excesses (up to 94% ee) under optimized conditions.

An asymmetriccarbenoidinsertion into S–H bonds catalyzed by copper–chiral spiro bisoxazoline complexes has been developed, in which a series of α-mercaptoesters were produced in high yields with moderate to good enantioselectivities (up to 85% ee); this result represents the best enantioselectivity in the catalytic asymmetriccarbenoid S–H bond insertion reaction.