Transfer hydrogenation process and catalyst

A process for the transfer hydrogenation of a compound of formula (1) to produce a compound of formula (2);

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• wherein:
• X represents CR3R4, NR5, (NR5R6)+Q−, O or S;
• R1, R2, R3, R4, R5 and R6each independently represents a hydrogen atom, an optionally substituted hydrocarbyl, a perhalogenated hydrocarbyl or an optionally substituted heterocyclyl group, one or more of R1 & R2, R1 & R3, R2 & R4, R3 & R4, R1 & R5, R2 & R6 and R5 & R6 optionally being linked in such a way as to form an optionally substituted ring(s);
• and
• Q− represents an anion;
• said process comprising reacting the compound of formula (1) with a hydrogen donor in the presence of a catalyst, characterised in that the catalyst has the general formula:
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• wherein:
• R7 represents an optionally substituted cyclopentadienyl group;
• A represents —NR8—, —NR9—, —NHR8 or —NR8R9 where R8 is H, C(O)R10, SO2R10, C(O)NR10R14, C(S)NR10R14, C(═NR14)SR15 or C(═NR14)OR15, R9 and R10 each independently represents an optionally substituted hydrocarbyl, perhalogenated hydrocarbyl or an optionally substituted heterocyclyl group, and R14 and R15 are each independently hydrogen or a group as defined for R10;
• B represents —O—, —OH, OR11, —S—, —SH, SR11, —NR11—, —NR12—, —NHR12 or —NR11R12 where R12 is H, C(O)R13, SO2R13, C(O)NR13R16, C(S)NR13R16, C(═NR16)SR17 or C(═NR16)OR17, R11 and R13 each independently represents an optionally substituted hydrocarbyl, perhalogenated hydrocarbyl or an optionally substituted heterocyclyl group, and R16 and R17 are each independently hydrogen or a group as defined for R13;
• E represents a linking group;
• M represents a metal capable of catalysing transfer hydrogenation;
• and
• Y represents an anionic group, a basic ligand or a vacant site;
• provided that when Y is not a vacant site that at least one of A or B carries a hydrogen atom.