The Search for Divalent Carbon Compounds

The door to isolable carbenes was partially opened by Hans-Werner Wanz-lick from the Technische Universitat in Berlin. In 1970, he postulated that the 

1 In English I think the ways by which people gain knowledge, are almost as wonderful as the nature of the things themselves 

Werner, Landmarks in Organo-Transition Metal Chemistry, Profiles in Inorganic Chemistry, DOI 10.1007/978-0-387-09848-7 8, Springer Science-1-Business Media, LLC 2009 

Universitat in Miinchen (for his studies on arene chromium tricarbonyls see Chap. 5) prepared the diaminocarbene chromium pentacarbonyl 9 from the imidazolium salt 8 by heating the starting material at 120°C [13]. Although Wanzlick s and Ofele s results received considerable attention, the opportunity to isolate stable carbenes was missed. 

2 From Wanzlick s and Ofele s Work to Arduengo s Carbenes 

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