Bis(alkyl) complexes [(2,6‐Me2C6H3)NC(tBu)N(C6H4−2‐OMe)]M(CH2C6H4−2‐NMe2)2 (M=Sc (4), Y (5)), [(2‐OMe−C6H4N)2C(tBu)]Y(CH2SiMe3)2(THF)2 (6), supported by N,N,O‐tridentate (4, 5) and N,N,O,O‐tetradentate (6) amidinate ligands were synthesized by the alkane elimination approach reacting tris(alkyl) rare‐earth species M(R)3Xn (R=Me3SiCH2, X=THF, n=2; R=CH2C6H4−2‐NMe2, n=0) with one equivalent of amidine (2,6‐Me2C6H3)N=C(tBu)−NH(C6H4−2‐OMe) (1) or (2‐MeO−C6H4)N=C(tBu)−NH(C6H4−2‐OMe) (2). The reaction of amidine 2 with equimolar amount of Y(CH2C6H4−2‐NMe2)3 in toluene unexpectedly results in the addition of N,N‐dimethylaminobenzyl group to C=N bond of one amidinate fragment, ligand disproportionation and the formation of novel bis(amide)amidinate complex [(2‐OMe−C6H4N)2C(tBu)CH2C6H4−2‐NMe2]Y[(2‐OMe−C6H4N)2C(tBu)] (7). Complexes 4–6 were evaluated as catalysts for α‐olefins and isoprene polymerization.