93598-64-2

Upstream product

• 201230-82-2 carbon monoxide 
• 3893-35-4 1-diazo-1-phenyl-2-propanone 
• 538-51-2 benzylidene phenylamine 
• 87769-42-4 5-phenyl-2,2,6-trimethyl-2h,4h-1,3-dioxin-4-one 
• 1750-36-3 (E)-N-benzylidenebenzenamine 

Relevant academic research and scientific papers

Pd-catalyzed carbonylation of diazo compounds at atmospheric pressure: A catalytic approach to ketenes

The carbonylation of carbenes through catalytic cycles is highly desirable due to the importance of ketene-mediated reactions in organic synthesis. In this investigation, a highly efficient and mild catalytic approach toward ketene intermediates has been developed based on Pd-catalyzed carbonylation of diazo compounds with CO. When α-diazocarbonyl compounds or N-tosylhydrazone salts are heated in the presence of a palladium catalyst under atmospheric pressure of CO, ketene intermediates are formed in situ, where they undergo further reactions with various nucleophiles such as alcohols, amines, or imines. The Pd-catalyzed tandem carbonylation-Staudinger cycloaddition gives β-lactam derivatives in good yields with excellent trans diastereoselectivity. The results from DFT calculation on the reaction mechanism suggest that Pd is involved in the [2 + 2] cycloaddition process and affects the diastereoselectivity of the β-lactam products by assisting isomerization of the addition intermediate. On the other hand, the acylketenes generated from the Pd-catalyzed carbonylation of α-diazoketones react with imines in a formal [4 + 2] cycloaddition manner to afford 1,3-dioxin-4-one derivatives. This straightforward carbonylation provides a new approach toward highly efficient catalytic generation of ketene species under mild conditions.

Reaction of 2,2-dimethyl-1,3-dioxin-4-ones with Imines, Carbodiimides, and Isocyanates

The ring transformation of 2,2-dimethyl-1,3-dioxin-4-ones (1) to nitrogen heterocycles was studied.Heating of 1 whith imines such as Schiff bases gave rise to cycloadducts of imines to acylketenes (2), i.e., 3,4-dihydro-1,3-oxazin-4-one derivatives