Nacnac-based tridentate ligands containing a pyridyl-methyl and a 2,6-dialkyl-phenylamine (i.e., (2,6-R-2-C6H3N=C(Me)CH=C(Me)NH(CH(2)py); R = Et, {Et(nn)PM}H; R = Pr-i, {Pr-i(nn)PM}H) were synthesized by condensation routes. Treatment of M{N(TMS)(2)}THFn (M = Cr, n = 2; M = Fe, Co, n = 1; TMS = trimethylsilane; THF = tetrahydrofuran) with {Pr-i(nn)PM}H) afforded {Pr-i(nn)PM}MN(TMS)(2) (1-M-iPr; M = Cr, Fe); {Et(nn)PM}MN(TMS)(2) (1-M-Et; M = Fe, Co) was similarly obtained. {R(nn)PM}FeBr (R = Pr-i, Et; 2-Fe-R) were prepared from FeBr2 and {R(nn)PM}Li, and alkylated to generate {R(nn)PM}Fe(neo)Pe (R = Pr-i, Et; 3-Fe-R). Carbonylation of 3-Fe-R provided {Pr-i(nn)PM}Fe(CO(neo)Pe)CO (4-Fe-iPr), and carbonylations of 1-Fe-R (R = Et, Pr-i) and 1-Ce-iPr induced deamination to afford {R(nn)PI}Fe(CO)(2) (R = Pr-i, 5-Fe-iPr; Et, 5-Fe-Et), where PI is pyridine-imine, and {kappa(2)-N,N-pyrim-pyr}Cr(CO)(4) (6-Cr-iPr), in which the aryl-amide side of the nacnac attacked the incipient PI group. Carbon-carbon bonds were formed at the imine carbon of the {R(nn)PI} ligand. Addition of [{Pr-i(nn)PI}(2-)](K+(THF)(x))(2) to FeCl3 generated {Pr-i(nn)CHpy}(2)Fe2Cl2 (7-Fe-iPr), and TMSN3 induced the deamination of 1-Fe-Et, but with disproportionation to provide {[Et(nn)CHpy](2)}Fe (8-Fe-Et). Ph2CN2 induced C-C bond formation with 1-Fe-iPr via its thermal degradation to ultimately afford {Pr-i(nn)CHpy}(2)(FeN=CPh2)(2) (9-Fe-iPr). The compounds were examined by X-ray crystallography (1-M-iPr, M = Cr, Fe; 1-Co-Et; 2-Fe-iPr; 4-Fe-iPr; 5-Fe-iPr; 6-Cr-iPr; 7-Fe-Et; 8-Fe-Et; 9-Fe-iPr), Mossbauer spectroscopy, and NMR spectroscopy. Structural parameters assessing redox noninnocence are discussed, as are structural and mechanistic consequences of the various electronic environments.