Ruthenium-Catalyzed Chemo-Selective Carbene Insertion into C-H Bond of Styrene over Cyclopropanation: C-C Bond Formation.

The C-C bond formation reactions are important in organic synthesis. Heck reaction is known to arylate the terminal carbon of olefins; however, direct alkylation of the terminal carbon of olefin is limited. Herein, we report a novel ruthenium-catalyzed selective cross-coupling reaction of styrene and α-diazoesters to form a new C-C bond over cyclopropanation via the C-H insertion process for the first time.

Synthesis of β-Lactams through Carbonylation of Diazo Compounds Followed by the [2 + 2] Cycloaddition Reaction.

Reporting an efficient method for the synthesis of β-lactams by the carbonylation of diazo compounds, using [Co(CO)] to corresponding ketenes, followed by [2 + 2] cycloaddition with imines. The newly developed strategy was successfully applied to electronically and structurally diverse substrates to produce the corresponding β-lactams under mild reaction conditions. Fourier transform infrared spectroscopy was employed to monitor ketene formation and the transformation of ketene into β-lactam.

Carboxylic Acid Functionalization Using Sulfoxonium Ylides as a Carbene Source.

Functionalization of carboxylic acids using sulfoxonium ylides in the presence of [VO(acac)] as a catalyst is reported. The usual carbene source, diazo compounds, failed to produce α-carbonyloxy esters in good yield when compared to sulfoxonium ylides. Various standard spectroscopic and analytical techniques were used to characterize the products formed.