Wulff-Dotz reaction

Analysis of product distributions has often been used to evince the presence of 774-vinylketenes in the Dotz reaction. Wulff has studied the reactions of a wide variety of substituted aryl chromiumcarbenes and drawn conclusions from the data that point directly toward i74-vinylketene complexes as key intermediates.13 He has also isolated40 bicyclic lactone products (e.g., 23) characteristic of a van Halban-White cyclization41-44 from the reaction of vinylcarbenes and ketoalkynes. These bicyclic lactones are not generally... 

E. O. Fischer and K. H. Dotz, Chem. Ber., 1972, 105, 3966 for a more recent paper on reactions of Fischer carbene complexes with electron-rich alkenes, see W. D. Wulff, D. C. Yang, and C. K. Murray, PureAppl. Chem., 1988, 60, 137. 

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