2-Diazonio-1,3-dimethoxy-3-oxoprop-1-en-1-olate → HCID 59255985, compound

Participants

Reaction Steps

In a round-bottomed flask, 3-(3,4-dichlorophenyl)-3-buten-1-yl methanesulfonate (P62, 90.8 g, 308 mmol) was dissolved in chlorobenzene (200 ml) to give a green solution. Rhodium acetate dimer (6.80 g, 15.38 mmol) was added. The suspension was warmed to an internal temperature of +65° C. and dimethyl diazopropanedioate (78 g, 492 mmol, for a reference procedure of preparation see Synthetic Communication 1987, 17 (14), 1709-1716) dissolved in chlorobenzene (150 ml) was added dropwise (during 2.5 hrs), keeping the internal temperature below 65-67° C. At the end of the addition, the mixture was cooled to room temperature. It was diluted with DCM (300 ml) and filtered over a celite pad to separate the catalyst.

Provenance & Evidence