The reaction of [ircla(tht)s] (tht-tetrahydrothiophene) with allyllithium gave a neutral organometallic complex, compound a which does not have cl or tht ligands. compound a was found to undergo addition reactions with: (a) 1 mol of pphs to give compound b and (b) 2 mols of pme3 to give compound c. compounds a, b and c obey the 18 electron rule. draw the structures of compounds a, b and c clearly indicating mode of bonding of ligands involved reference paper: k. d. john, k. v. salazar, b. l. scott, r. t. baker and a. p. sattelberger, "chemistry of m(allyl)3 (m rh, ir) compounds: structural characterization of tris(allyl)iridium complexes with phosphorus ligands". chem. commun, 2000, 581-582