Takahiro Kimura’s research while affiliated with Kyoto University and other places

... Compound 9 was then protected as a Bocsulfonamide by treatment with di-(tert-butyl)dicarbonate in CH 2 Cl 2 using 4- (dimethylamino)pyridine (DMAP) as acylation catalyst [22]. The N-protected intermediate 10 was submitted to the Sonogashira reaction [23,24] in the presence of Pd(II), CuI, triphenylphosphine and triethylamine to afford the acetylenic derivative 11. Acid hydrolysis with TFA allowed to deprotect the carboxylic acid and the sulfonamidic nitrogen in a single step. ...

Reference:

Synthesis and Biological Evaluation in U87MG Glioma Cells of (Ethynylthiophene)Sulfonamido-Based Hydroxamates as Matrix Metalloproteinase Inhibitors

... The 1 H NMR spectroscopic data matched that for an alternative preparation of (R)-19g. 116 Data for 19g: bp 75 °C ABT (0.03 mmHg). ...

Reference:

ChemInform Abstract: Iron-Catalyzed Cross-Coupling of Unactivated Secondary Alkyl Thio Ethers and Sulfones with Aryl Grignard Reagents.

... 6 Intermolecular strategies typically center on conjugate addition reactions of organometallic reagents, such as Grignard reagents and organozinc reagents, to 4-quinolones. 7,8 While high enantiocontrol can be achieved in these cases, these methods generally suffer from the use of sensitive reagents as well as expensive or non-commercially available ligands. With such limits of available methodologies, we hypothesized that an alkynylation reaction of 4-siloxyquinolinium triflates, reactive species generated in situ from quinolones, could give rise to a straightforward, robust, and highly enantioselective synthesis of desirable dihydroquinolones. ...

Reference:

Highly Enantioselective Catalytic Alkynylation of Quinolones: Substrate Scope, Mechanistic Studies, and Applications in the Syntheses of Chiral N -Heterocyclic Alkaloids and Diamines

... The most widely used transformations of this type include Zr-catalyzed Negishi methylamination, 1 -3 cycloalumination, 4 -7 Dzhemilev cyclomagnesiation, 8 -13 carbocupration, 14 carbostannylation, 15 carboboration, 16,17 and arylmagnesiation. 18 The carbometallation of alkynes with organozinc reagents is one of the most popular approaches to the synthesis of various functionally substituted alkenes. 19 -28 The considerable interest in the organozinc synthesis of these olefins is, first of all, due to the tolerance of Zn reagents to the presence of heterofuctional substituents in the substrates containing triple bonds. ...

Reference:

Catalytic carbozincation of acetylenic compoundscatalyzed by transition metal complexes

... Only triflate 11 was isolated as a solution in tetrahydrofuran (THF) (Scheme 5). The vinylation of alkynylmagnesium bromide 14 can be performed using vinyl nonaflate in the presence of a cobalt catalyst to produce enyne 15 (Scheme 6) [108]. The optimized reaction conditions have a significantly broader scope, although enyne 15 was prepared in a near-quantitative isolated yield. ...

Reference:

Vinyl Esters and Vinyl Sulfonates as Green Alternatives to Vinyl Bromide for the Synthesis of Monosubstituted Alkenes via Transition-Metal-Catalyzed Reactions