Potassium carbonylferrate

Conjugate reduction of enones. The alkali metal carbonylchromates reduce a, -unsaturated carbonyl compounds to the corresponding saturated carbonyl compounds in 4d-807o yield. They are comparable to potassium hydridotetra-carbonylferrate (6, 483-486), but are simpler to prepare because chromium hexacarbonyl is a stable solid and less toxic than iron pentacarbonyl. Examples ... 

The formation of an acylated phosphine was accomplished via the reaction of chlorodiphenylphosphine with a carbonylferrate. The proposed pathway is shown in Scheme 39. Similarly, reactions employing C1P(NR2)2 led ultimately to insertion of the P(NR2)2 fragment into the Fe-FI bond (Equation (57)). Reactions between KHFe(CO)4 and amino-substituted phosphines were reported. Reactions with tris(amino)phosphines, proceeding via activation of a P-N bond, are shown in Equation (58). Reactions of these products with an excess of potassium hydride resulted in the formation of phosphido complexes (Equation (59)), which react with either methyl iodide or acetyl chloride to alkylate/acylate the phosphorus atom. 

The direct conversion of homoallylic alcohols (15) into a-methyl-enebutyrolactones (16) has been achieved using [Ni(CO)4] in the presence of a base. The choice of base appears to be very important since in the presence of potassium acetate yields are around 60% whereas on using sodium methoxide yields drop to only 4%. Other carbonylating systems, e.g. disodium tetra-carbonylferrate and Co-[PdCl2(Ph3P)2], are ineffective. 

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