Process for the hydroconversion of a low quality hydrocarbonaceous feedstock

Process for the hydroconversion of a low quality hydrocarbonaceous feedstock using an active slurry catalytic phase, wherein said active slurry catalytic phase is obtained from a precursor composition comprising at least one organometallic coordination compound of formula C1C2MLn (I), where

• M is a transition metal selected from group IIA, IIIB, IVB, VB, VIIB, VIIB, VIII, IB or IIB of the periodic table of elements,
• —C1 and —C2 are monocyclic or polycyclic aryl hydrocarbon ligands that are pi-bonded to M, —C1 and —C2 being the same or different, each of —C1 or —C2 comprising from 0 to 5 substituents R, each substituent R being the same or different, R being selected from:
• a C3-C8 substituted or unsubstituted, monocyclic or polycyclic ring structure that is partially unsaturated, unsaturated or aromatic, fused or not fused to the ligand —C1 or —C2,
• a C3-C8 substituted or unsubstituted, partially unsaturated or unsaturated, linear or branched, alicyclic hydrocarbyl radical,
• a C1-C8, substituted or unsubstituted, linear or branched, saturated hydrocarbyl radical,
• —C1 and —C2 being independent or connected via at least one substituent R,
• -L is a ligand that is sigma-bonded to M, n is an integer equal to 0 to 3, each -L is, independently, a univalent ligand.