From Alkyl Complexes by a-Abstraction

This methodology has proven particularly useful for preparing non-heteroatom-stabilized carbene complexes (Section 3.1.2), but is also suitable for certain types of heteroatom-substituted carbene complex [177] (Table 2.9). 

Experimental Procedure 2.1.3. Preparation of an Iron Carbene Complex by a-Abstraction of Hydride Dicarbonyl(T 5-cyclopentadienyl)(phenylthiocarbene) iron hexafluorophosphate [179] 

Sodium amalgam is prepared by slowly adding small pieces of freshly cut sodium (2.0 g, 87 nunol) to stirred mercury (14 mL, 190g, 0.95 mol) under inert gas (caution exomermic reaction). When the amalgam has cooled to room temperature a solution of [Cp(CO)2Fe]j (10.0 g, 28.3 mmol) in dry, degassed THF (150 mL) is added and the resulting mixture is stirred at room temperature 

---

Many non-heteroatom-substituted carbene complexes have been prepared from alkyl complexes by a-abstraction, for which two mechanistically different pathways must be considered (Figure 3.3) ... 

---