Tungsten complexes alkyl alkoxy

Tungsten complexes, 3, 973-1015 alkoxy carbonyl reactions, 2, 355 alkyl alkoxy reactions, 2, 358 amides... 

The metal, M, can be Fe, Ru, Os (with n = 4) or Cr (n = 5). Substituents on silicon can vary widely, including aryl, alkyl, alkoxy and Et2N groups. With a slight modification, the same reaction is useful for silylene-tungsten complexes (equation 98). 

Nucleophilic acyl complexes can be 0-alkylated with hard electrophiles to yield the corresponding alkoxy- or (acyloxy)carbene complexes. The first carbene complex ever isolated [61] was prepared by this route the intermediate, anionic acyl complex was generated by addition of phenyllithium to tungsten hexacarbonyl (Figure 2.3). 

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