Bortoluzzi Marco, Hayatifar Mohammad, Marchetti Fabio, Pampaloni Guido, Zacchini Stefano
†Dipartimento di Scienze Molecolari e Nanosistemi, Ca' Foscari Università di Venezia, Dorsoduro 2137, 30123 Venezia, Italy.
§Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, Viale Risorgimento 4, I-40136 Bologna, Italy.
Inorg Chem. 2015 Apr 20;54(8):4047-55. doi: 10.1021/acs.inorgchem.5b00286. Epub 2015 Apr 6.
Dinuclear complexes of formula Nb2Cl9[O2CCH(R)NR'R″2-κO,κO] (R = CH2CHMe2, R' = R″ = H, 1a; R = CH2Ph, R' = R″ = H, 1b; R = CH2CH2SCH3, R' = R″ = H, 1c; R = R' = H, R″ = Me, 1d; R = CH2Ph, R' = R″ = Me, 1e; Nb2Cl9[O2C⌈CH(CH2)3NH⌉], 1f) were prepared by allowing NbCl5 to react in dichloromethane with the appropriate α-amino acid in 1:2 amino acid/Nb molar ratio. The 1:1 reactions between MX5 (M = Nb, Ta; X = Cl, Br) and a series of α-amino acids resulted in the formation of the iminium salts [(R)CH═NR'R″2][MX6] (R = CH2Ph, R' = R″ = Me: M = Nb, X = Cl, 2a; M = Nb, X = Br, 2b; M = Ta, X = Cl, 2c; M = Ta, X = Br, 2d; R = CH2Ph, R' = R″ = H, M = Nb: X = Cl, 3a; X = Br, 3b; R = CH2CHMe2, R' = R″ = H, M = Nb, X = Cl, 4; R = R' = H, R″ = Me, M = Nb, X = Cl, 5). The formate/amino acidate derivative NbCl3(O2CH)[O2CCH(CH2Ph)NMe2], 6, was isolated and identified as coproduct of the 1:1 reaction between NbCl5 and N,N-dimethyl-l-phenylalanine, leading to 2a. All of the compounds were characterized by analytical and spectroscopic methods and by X-ray diffractometry in the cases of 2a, 2b, and 2d. Moreover, density functional theory studies were carried out to shed light on mechanistic and structural aspects.
通过使五氯化铌在二氯甲烷中与适当的α-氨基酸以1:2（氨基酸/铌）摩尔比反应，制备了通式为Nb₂Cl₉[O₂CCH(R)NR'R″₂-κO,κO]的双核配合物（R = CH₂CHMe₂，R' = R″ = H，1a；R = CH₂Ph，R' = R″ = H，1b；R = CH₂CH₂SCH₃，R' = R″ = H，1c；R = R' = H，R″ = Me，1d；R = CH₂Ph，R' = R″ = Me，1e；Nb₂Cl₉[O₂C⌈CH(CH₂)₃NH⌉]，1f）。MX₅（M = Nb，Ta；X = Cl，Br）与一系列α-氨基酸的1:1反应生成了亚胺鎓盐[(R)CH═NR'R″₂][MX₆]（R = CH₂Ph，R' = R″ = Me：M = Nb，X = Cl，2a；M = Nb，X = Br，2b；M = Ta，X = Cl，2c；M = Ta，X = Br，2d；R = CH₂Ph，R' = R″ = H，M = Nb：X = Cl，3a；X = Br，3b；R = CH₂CHMe₂，R' = R″ = H，M = Nb，X = Cl，4；R = R' = H，R″ = Me，M = Nb，X = Cl，5）。分离并鉴定了甲酸盐/氨基酸盐衍生物NbCl₃(O₂CH)[O₂CCH(CH₂Ph)NMe₂]，6，它是五氯化铌与N,N-二甲基-L-苯丙氨酸1:1反应生成2a时的副产物。所有化合物均通过分析和光谱方法进行了表征，对于2a、2b和2d，还通过X射线衍射法进行了表征。此外，还进行了密度泛函理论研究以阐明其机理和结构方面。
