Platinum( ii ) alkyl complexes of chelating dibridgehead diphosphines P((CH 2 ) n ) 3 P ( n = 14, 18, 22); facile cis / trans isomerizations interconverting gyroscope and parachute like adducts
Platinum( ii ) alkyl complexes of chelating dibridgehead diphosphines P((CH 2 ) n ) 3 P ( n = 14, 18, 22); facile cis / trans isomerizations interconverting gyroscope and parachute like adducts
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螯合双桥头二膦 P((CH 2 ) n ) 3 P ( n = 14, 18, 22) 的铂( ii )烷基络合物；
DOI：
10.1039/d1dt02321g
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发表时间：
2021
影响因子：
4
通讯作者：
Gladysz, John A.
中科院分区：
文献类型：
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作者：
Zhu, Yun;Ehnbom, Andreas;Fiedler, Tobias;Shu, Yi;Bhuvanesh, Nattamai;Hall, Michael B.;Gladysz, John A.
陀螺样二氯化物配合物trans-Pt（Cl）2（P（（CH 2）n）3 P）（trans-2; n = c，14; e，18; g，22）和MeLi（2当量）。反应生成降落伞状的二甲基配合物cis-Pt（Me）2（P（（CH 2）n）3 P）（cis-4c，例如，70-91%）。HCl（1当量）与顺式-4c反应得到顺式-Pt（Cl）（Me）（P（（CH 2）14）3 P）（顺式-5c，83%），其在与硅胶搅拌或结晶时得到反式-5c（89%）。HCl和顺式-4e，g的类似反应得到顺式/反式-5e，g混合物，其在与硅胶一起搅拌时得到反式-5e，g。与trans-2c/EtLi的平行顺序得到cis-Pt（Et）2（P（（CH 2）14）3 P）（cis-6c，85%），但随后与HCl反应直接得到trans-Pt（Cl）（Et）（P（（CH 2）14）3 P）（trans-7 c，45%）。当先前报道的顺式-Pt（Ph）2（P（（CH 2）14）3 P）用HCl（1当量）处理时，分离出顺式和反式Pt（Cl）（Ph）（P（（CH 2）14）3 P）（44%，29%），前者在100 °C下转化为后者。trans-5c与LiBr或NaI反应得到卤代配合物trans-Pt（X）（Me）（P（（CH 2）14）3 P）（trans-9 c，88%; trans-10 c，87%）。理论和DFT计算，包括非环状模型化合物建立反式>顺式的稳定性，除了二烷基络合物，其能量可以紧密间隔。非膦配体的σ给体强度在趋势中被指定为关键角色。测定了cis-4c、trans-5c、trans-7 c和trans-10 c的晶体结构，并与计算结构一起进行了分析。
The gyroscope like dichloride complexes trans-Pt(Cl)2(P((CH2)n)3P) (trans-2; n = c, 14; e, 18; g, 22) and MeLi (2 equiv.) react to yield the parachute like dimethyl complexes cis-Pt(Me)2(P((CH2)n)3P) (cis-4c,e,g, 70–91%). HCl (1 equiv.) and cis-4c react to give cis-Pt(Cl)(Me)(P((CH2)14)3P) (cis-5c, 83%), which upon stirring with silica gel or crystallization affords trans-5c (89%). Similar reactions of HCl and cis-4e,g give cis/trans-5e,g mixtures that upon stirring with silica gel yield trans-5e,g. A parallel sequence with trans-2c/EtLi gives cis-Pt(Et)2(P((CH2)14)3P) (cis-6c, 85%) but subsequent reaction with HCl affords trans-Pt(Cl)(Et)(P((CH2)14)3P) (trans-7c, 45%) directly. When previously reported cis-Pt(Ph)2(P((CH2)14)3P) is treated with HCl (1 equiv.), cis- and trans-Pt(Cl)(Ph)(P((CH2)14)3P) are isolated (44%, 29%), with the former converting to the latter at 100 °C. Reactions of trans-5c and LiBr or NaI afford the halide complexes trans-Pt(X)(Me)(P((CH2)14)3P) (trans-9c, 88%; trans-10c, 87%). Thermolyses and DFT calculations that include acyclic model compounds establish trans > cis stabilities for all except the dialkyl complexes, for which energies can be closely spaced. The σ donor strengths of the non-phosphine ligands are assigned key roles in the trends. The crystal structures of cis-4c, trans-5c, trans-7c, and trans-10c are determined and analyzed together with the computed structures.