Thompson David W, Kretzer Ryan M, Lebeau Estelle L, Scaltrito Donald V, Ghiladi Reza A, Lam Kin-Chung, Rheingold Arnold L, Karlin Kenneth D, Meyer Gerald J
Department of Chemistry, The Johns Hopkins University, Charles and 34th Streets, Baltimore, Maryland 21218, USA.
Inorg Chem. 2003 Aug 25;42(17):5211-8. doi: 10.1021/ic026307b.
We present here the synthesis, characterization, and flash photolysis study of [(F(8)TPP)Fe(II)(CO)(THF)] (1) [F(8)TPP = tetrakis(2,6-difluorophenyl)porphyrinate(2-)]. Complex 1 crystallizes from THF/heptane solvent system as a tris-THF solvate, [(F(8)TPP)Fe(II)(CO)(THF)].3THF (1.3THF), with ferrous ion in the porphyrin plane (C(61)H(52)F(8)FeN(4)O(5); a = 11.7908(2) A, b = 20.4453(2) A, c = 39.9423(3), alpha = 90 degrees, beta = 90 degrees, gamma = 90 degrees; orthorhombic, P2(1)2(1)2(1), Z = 8; Fe-N(4)(av) = 2.00 A; N-Fe-N (all) = 90.0 degrees ). This complex (as 1.THF) has also been characterized by (1)H NMR [six-coordinate, low-spin heme; CD(3)CN, RT, delta 8.82 (s, pyrrole-H, 8H), 7.89 (s, para-phenyl-H, 8H), 7.46 (s, meta-phenyl-H, 4H), 3.58 (s, THF, 8H), 1.73 (s, THF, 8H)], (2)H NMR (pyrrole-deuterated analogue) [(F(8)TPP-d(8))Fe(II)(CO)(THF)] [THF, RT, delta 8.78 ppm (s, pyrrole-D)], (13)C NMR (on (13)CO-enriched adduct) [THF-d(8), RT, delta 206.5 ppm; CD(2)Cl(2), RT, delta 206.1 ppm], UV-vis [THF, RT, lambda(max), 411 (Soret), 525 nm], and IR [293 K, solution, nu(CO) 1979 cm(-)(1) (THF), 1976 cm(-)(1) (acetone), 1982 cm(-)(1) (CH(3)CN)] spectroscopies. In order to more fully understand the intricacies of solvent-ligand binding (as compared to CO rebinding to the photolyzed heme), we have also synthesized the bis-THF adduct [(F(8)TPP)Fe(II)(THF)(2)]. Complex 2 also crystallizes from THF/heptane solvent system as a bis-THF solvate, [(F(8)TPP)Fe(II)(THF)(2)].2THF (2.2THF), with ferrous iron in the porphyrin plane (C(60)H(52)F(8)FeN(4)O(4); a = 21.3216(3) A, b = 12.1191(2) A, c = 21.0125(2) A, alpha = 90 degrees, beta = 105.3658(5) degrees, gamma = 90 degrees; monoclinic, C2/c, Z = 4; Fe-N(4)(av) = 2.07 A; N-Fe-N (all) = 90.0 degrees ). Further characterization of 2 includes UV-vis [THF, lambda(max), 421 (Soret), 542 nm] and (1)H NMR [six-coordinate, high spin heme; THF-d(8), RT, delta 56.7 (s, pyrrole-H, 8H), 8.38 (s, para-phenyl-H, 8H), 7.15 (s, meta-phenyl-H, 4H)] spectroscopies. Flash photolysis studies employing 1 were able to resolve the CO rebinding kinetics in both THF and cyclohexane solvents. In CO saturated THF [[CO] approximately 5 mM] and at [1] congruent with 5 microM, the conversion of [(F(8)TPP)Fe(II)(THF)(2)] (produced after photolytic displacement of CO) to [(F(8)TPP)Fe(II)(CO)(THF)] was monoexponential, with k(obs) = 1.6 (+/-0.2) x 10(4) s(-)(1). Reduction in [CO] by vigorous Ar purging gave k(obs) congruent with 10(3) s(-)(1) in cyclohexane. The study presented in this report lays the foundation for applying fast-time scale studies based on CO flash photolysis to the more complicated heterobimetallic heme/Cu systems.
我们在此展示了[(F(8)TPP)Fe(II)(CO)(THF)] (1) [F(8)TPP = 四(2,6 - 二氟苯基)卟啉(2 - )]的合成、表征及闪光光解研究。配合物1从THF/庚烷溶剂体系中结晶为三THF溶剂化物，即[(F(8)TPP)Fe(II)(CO)(THF)].3THF (1.3THF)，亚铁离子处于卟啉平面内(C(61)H(52)F(8)FeN(4)O(5); a = 11.7908(2) Å, b = 20.4453(2) Å, c = 39.9423(3)，α = 90°，β = 90°，γ = 90°; 正交晶系，P2(1)2(1)2(1)，Z = 8; Fe - N(4)(av) = 2.00 Å; N - Fe - N (所有) = 90.0°)。该配合物(以1.THF形式)还通过(1)H NMR [六配位，低自旋血红素; CD(3)CN，室温，δ 8.82 (单峰，吡咯 - H，8H)，7.89 (单峰，对 - 苯基 - H，8H)，7.46 (单峰，间 - 苯基 - H，4H)，3.58 (单峰，THF，8H)，1.73 (单峰，THF，8H)]、(2)H NMR (吡咯 - 氘代类似物) [(F(8)TPP - d(8))Fe(II)(CO)(THF)] [THF，室温，δ 8.78 ppm (单峰，吡咯 - D)]、(13)C NMR (在(13)CO富集加合物上) [THF - d(8)，室温，δ 206.5 ppm; CD(2)Cl(2)，室温，δ 206.1 ppm]、紫外 - 可见光谱[THF，室温，λ(max)，411 (Soret)，525 nm]以及红外光谱[293 K，溶液，ν(CO) 1979 cm(-)(1) (THF)，1976 cm(-)(1) (丙酮)，1982 cm(-)(1) (CH(3)CN)]进行了表征。为了更全面地理解溶剂 - 配体结合的复杂性(与CO重新结合到光解后的血红素相比)，我们还合成了双THF加合物[(F(8)TPP)Fe(II)(THF)(2)]。配合物2也从THF/庚烷溶剂体系中结晶为双THF溶剂化物，即[(F(8)TPP)Fe(II)(THF)(2)].2THF (2.2THF)，亚铁离子处于卟啉平面内(C(60)H(52)F(8)FeN(4)O(4); a = 21.3216(3) Å, b = 12.1191(2) Å, c = 21.0125(2) Å，α = 90°，β = 105.3658(5)°，γ = 90°; 单斜晶系，C2/c，Z = 4; Fe - N(4)(av) = 2.07 Å; N - Fe - N (所有) = 90.0°)。对2的进一步表征包括紫外 - 可见光谱[THF，λ(max)，421 (Soret)，542 nm]以及(1)H NMR [六配位，高自旋血红素; THF - d(8)，室温，δ 56.7 (单峰，吡咯 - H，8H)，8.38 (单峰，对 - 苯基 - H，8H)，7.15 (单峰，间 - 苯基 - H，4H)]光谱。使用1进行的闪光光解研究能够解析THF和环己烷溶剂中CO重新结合的动力学。在CO饱和的THF [[CO]约为5 mM]且[1]约为5 μM时，[(F(8)TPP)Fe(II)(THF)(2)] (由光解取代CO后产生)转化为[(F(8)TPP)Fe(II)(CO)(THF)]是单指数的，k(obs) = 1.6 (+/-0.2) x 10(4) s(-)(1)。通过剧烈的Ar吹扫降低[CO]，在环己烷中k(obs)约为10(3) s(-)(1)。本报告中呈现的研究为将基于CO闪光光解的快速时间尺度研究应用于更复杂的异双核血红素/Cu体系奠定了基础。
Zotero 插件