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A new palladium-catalyzed domino approach for the synthesis of attractive spirocyclic indolines and dihydrobenzofurans was developed. The reaction proceeds through a sequential intramolecular Heck spirocyclization, remote C-H activation, and diazocarbonyl carbene insertion. Various spiroindolines and spirodihydrobenzofurans containing two quartenary carbon stereocenters were readily obtained in good to excellent yields. A preliminary study of asymmetric spirocyclization using chiral monophosphoramidite as a ligand was also conducted, enabling access to highly valuable chiral spiroindolines with up to 80% ee. [ABSTRACT FROM AUTHOR]

A new DTBP/Mg(NO3)2-mediated bicyclization cascade of o-arylalkynylanilines with secondary arylphosphine oxides has been developed, enabling dual C(sp2)-H functionalization along with the cleavage of the C-N bond. The combination between regioselective P-centered radical-triggered [3 + 2] cyclization and C-centered radical-induced cross-coupling in a one-pot manner delivered 27 examples of tribenzo[b,e,g]phosphindole oxides with generally high regioselectivity. A reasonable mechanism for forming such products involving radical addition-cyclization cascade is proposed. [ABSTRACT FROM AUTHOR]

With the use of a simple sulfur-olefin ligand, a highly enantioselective rhodium-catalyzed addition of arylboroxines to N,N-dimethylsulfamoyl-protected aldimines has been achieved, allowing access to a broad range of chiral diarylmethylamines in high yields (up to 98%) with uniformly excellent enantioselectivities (up to 99% ee). This catalyst system is also applicable to the arylation of N-tosyl arylimines. By utilizing this method, some biologically active molecules possessing a chiral 1-aryl-1,2,3,4-tetrahydroisoquinoline core such as Solifenacin and (S)-(+)-Cryptostyline II are facilely constructed. [ABSTRACT FROM AUTHOR]

The first example of nickel-catalyzed asymmetric Ullmann coupling of bis-ortho-substituted arylhalides is described. With the chiral BINOL-based monodentate phosphoramidite ligand, the reaction allows atropoenantioselective synthesis of a series of axially chiral tetra-ortho-substituted biaryl dials. By taking advantage on this asymmetric Ullman coupling as a key stereogenic axis-forming reaction, the formal synthesis of (+)-isoschizandrin was accomplished. [ABSTRACT FROM AUTHOR]

A novel iron-catalyzed intermolecular decarboxylative Csp3−Csp2coupling reaction using proline derivatives as starting materials is developed. In this process, a series of potentially useful ligands (tertiary aminonaphthol) for catalysis was obtained. [ABSTRACT FROM AUTHOR]

Herein, the first example using commercially available 2-bromo-3,3,3-trifluoropropene (BTP) as a radical acceptor has been reported. Taking advantage of this strategy, a wide range of secondary trifluoromethylated alkyl bromides were synthesized in good to excellent yields with broad functional group tolerance by using redox-active esters as a radical precursor. The practicality of this protocol was further demonstrated by diverse derivations and direct modification of biologically active molecules.

A rhodium-catalyzed asymmetric oxidative C-H/C-H cross-coupling reaction between 1-aryl isoquinolines and indolizines is disclosed. With a matched pair of SCpRh complex and chiral carboxylic acid, enantioselective two-fold C-H/C-H cross-coupling reactions between 1-aryl isoquinolines and indolizines provide a variety of axially chiral bi(hetero)aryls in excellent yields and enantioselectivity (up to 96% yield and 98% ee). Mechanistic studies suggest that both C-H cleavages are likely reversible.

We present herein a visible-light-induced [3 + 2] cycloaddition of a hypervalent iodine(III) reagent with α-ketoacids for the construction of 5-CF 3 -1,3,4-oxadiazoles that are of importance in medicinal chemistry. The reaction proceeds smoothly without a photocatalyst, metal, or additive under mild conditions. Different from the well-established trifluorodiazoethane (CF 3 CHN 2 ), the diazotrifluoroethyl radical [CF 3 C(·)N 2 ], a trifluoroethylcarbyne (CF 3 CĊ:) equivalent and an unusual CF 3 -containing building block, is involved in the present reaction system.

Genome mining of an indolocarbazole-type gene cluster from a marine-derived Nocardiopsis flavescens NA01583 strain led to the discovery of three new indolocarbazole alkaloids ( 1 - 3 ). Heterologous expression of the intact loo gene cluster in a surrogate host Streptomyces lividans K4-114 led to the successful production of 3 . Notably, compound 1 showed potent cytotoxic activities toward eight cancer cell lines with IC 50 values ranging from 41 to 283 nM.

A new palladium-catalyzed domino approach for the synthesis of attractive spirocyclic indolines and dihydrobenzofurans was developed. The reaction proceeds through a sequential intramolecular Heck spirocyclization, remote C-H activation, and diazocarbonyl carbene insertion. Various spiroindolines and spirodihydrobenzofurans containing two quartenary carbon stereocenters were readily obtained in good to excellent yields. A preliminary study of asymmetric spirocyclization using chiral monophosphoramidite as a ligand was also conducted, enabling access to highly valuable chiral spiroindolines with up to 80% ee.

A new DTBP/Mg(NO 3 ) 2 -mediated bicyclization cascade of o-arylalkynylanilines with secondary arylphosphine oxides has been developed, enabling dual C(sp 2 )-H functionalization along with the cleavage of the C-N bond. The combination between regioselective P-centered radical-triggered [3 + 2] cyclization and C-centered radical-induced cross-coupling in a one-pot manner delivered 27 examples of tribenzo[b,e,g]phosphindole oxides with generally high regioselectivity. A reasonable mechanism for forming such products involving radical addition-cyclization cascade is proposed.

An asymmetric dual-metal relay catalysis strategy that combines Rh/chiral sulfur-olefin-catalyzed enantioselective 1,2-addition with a Pd-catalyzed intramolecular C-O coupling has been developed. The method allows rapid and efficient synthesis of quaternary carbon-containing gem-diaryl benzofuran-3(2H)-ones in good yields in a highly enantioselective manner (up to 99% ee) through a simple one-pot cascade reaction.

With the use of a simple sulfur-olefin ligand, a highly enantioselective rhodium-catalyzed addition of arylboroxines to N,N-dimethylsulfamoyl-protected aldimines has been achieved, allowing access to a broad range of chiral diarylmethylamines in high yields (up to 98%) with uniformly excellent enantioselectivities (up to 99% ee). This catalyst system is also applicable to the arylation of N-tosyl arylimines. By utilizing this method, some biologically active molecules possessing a chiral 1-aryl-1,2,3,4-tetrahydroisoquinoline core such as Solifenacin and (S)-(+)-Cryptostyline II are facilely constructed.

A rhodium-catalyzed stepwise asymmetric 1,4- and 1,2-addition of arylboronic acids to α,β-unsaturated cyclic N-sulfonyl ketimines has been developed, providing a wide range of gem-diaryl-substituted chiral benzosulfamidates with high optical purities. C1-Symmetric chiral diene and branched chiral sulfur-olefin ligands were sequentially utilized in this double-arylation process for high stereocontrol. Further synthetic utility offers new opportunities for the facile construction of otherwise difficult to access polycyclic heterocycles.

A novel iron-catalyzed intermolecular decarboxylative Csp(3)-Csp(2) coupling reaction using proline derivatives as starting materials is developed. In this process, a series of potentially useful ligands (tertiary aminonaphthol) for catalysis was obtained.