Facultad de Química de San Sebastián, Universidad del País Vasco (UPV/EHU), Apdo. 1072, 20080 San Sebastián, Spain.
Dalton Trans. 2019 Mar 5;48(10):3300-3313. doi: 10.1039/c8dt04929g.
The reaction of [RhCl(COD)]2 (COD = 1,5-cyclooctadiene) with racemic PPh2(CH(Ph)CH2CHO) and pyridine (py) led to the oxidative addition of the aldehyde, and a single geometric isomer of [RhHCl(PPh2(CH(Ph)CH2CO))(py)2] (1), with hydride trans to chloride, was obtained as a mixture of two diastereomers in a 95 : 5 ratio; this was in agreement with density functional theory (DFT) calculations. In a chloroform solution, the exchange of hydride by chloride yielded [RhCl2(PPh2(CH(Ph)CH2CO))(py)2] (2) as a mixture of a kinetically preferred species, trans-py-2a, and two diastereomers, cis-Cl-2b' and cis-Cl-2b, with cis pyridines and a chloride trans to acyl; as predicted by the DFT calculations, the latter was the major species. Complex 1 reacted with racemic PPh2(CH(Ph)CH2CHO) or PPh2(o-C6H4CHO) to afford [RhHCl(PPh2(CH(Ph)CH2CO))(κ1-PPh2(CH(Ph)CH2CHO))(py)] (3) or [RhHCl(PPh2(o-C6H4CO))(κ1-PPh2(CH(Ph)CH2CHO))(py)] (4), respectively, both with a dangling alkylaldehyde. Diastereomeric mixtures with the ratios 3a/3a' = 80 : 20 and 4a/4a' = 50 : 50 were obtained. Complex 4 reacted with N-donors to afford cationic [RhH(NN)(PPh2(o-C6H4CO))(κ1-PPh2(CH(Ph)CH2CHO))]BPh4 (NN = 1,10-phenanthroline, 5; 2,2'-bipyridine, 6) or with 8-aminoquinoline (aqui) or 2-(aminomethyl)pyridine to yield imination products with terdentate ligands: [RhH(PPh2(o-C6H4CO))(κ3-PNN)]BF4 (PNN = PPh2(CH(Ph)CH2CNC9H6N), 7 and PPh2(CH(Ph)CH2CNCH2C5H4N), 8, respectively. Compounds 5-8 were obtained as equimolar a/a' mixtures of diastereomers. Moreover, 5a and 5a' could be separated. [RhCl(NBD)]2 reacted with racemic PPh2(CH(Ph)CH2CHO) and N-donors to provide nortricyclyl (Ntyl) derivatives [RhCl(NN)(Ntyl)(PPh2CH(Ph)CH2CO)] (NN = phen, 9 and bipy, 10) as an a/a' = 75 : 25 mixture of diastereomers. By reacting [RhCl(NBD)]2 with PPh2(CH(Ph)CH2CHO) and quinoline-8-carbaldehyde in methanol, the phosphino-ester complex [RhCl(Ntyl)(C9H6NCO)(κ2-PPh2CH(Ph)CH2CO(OCH3)] 11 was obtained. The initial equimolar mixture of two diastereomers readily transformed into a single diastereomer, which was found to be thermodynamically most stable by the DFT calculations. Furthermore, single crystal X-ray diffraction analysis of cis-Cl-2b, 5a, 7a, 10a and 11 is reported.
[RhCl(COD)]2（COD = 1,5-环辛二烯）与外消旋 PPh2(CH(Ph)CH2CHO) 和吡啶（py）反应导致醛的氧化加成，并且获得了一个单一的几何异构体[RhHCl(PPh2(CH(Ph)CH2CO))(py)2]（1），其中氢化物trans 到氯，作为两种非对映异构体的混合物获得，比例为 95：5；这与密度泛函理论（DFT）计算一致。在氯仿溶液中，通过氯交换氢化物得到[RhCl2(PPh2(CH(Ph)CH2CO))(py)2]（2）作为动力学上优选的物种 trans-py-2a 和两种非对映异构体 cis-Cl-2b'和 cis-Cl-2b 的混合物，其中 cis 吡啶和酰基 trans 到氯；正如 DFT 计算所预测的那样，后者是主要物种。复合物 1 与外消旋 PPh2(CH(Ph)CH2CHO)或 PPh2(o-C6H4CHO)反应，分别得到[RhHCl(PPh2(CH(Ph)CH2CO))(κ1-PPh2(CH(Ph)CH2CHO))(py)]（3）或[RhHCl(PPh2(o-C6H4CO))(κ1-PPh2(CH(Ph)CH2CHO))(py)]（4），两者均具有悬垂烷基醛。获得了具有 3a/3a'=80：20 和 4a/4a'=50：50 的非对映异构体混合物。复合物 4 与氮供体反应得到阳离子[RhH(NN)(PPh2(o-C6H4CO))(κ1-PPh2(CH(Ph)CH2CHO))]BPh4（NN = 1,10-菲咯啉，5；2,2'-联吡啶，6）或与 8-氨基喹啉（aqui）或 2-（氨甲基）吡啶反应，得到具有三齿配体的亚胺化产物：[RhH(PPh2(o-C6H4CO))(κ3-PNN)]BF4（PNN = PPh2(CH(Ph)CH2CNC9H6N)，7 和 PPh2(CH(Ph)CH2CNCH2C5H4N)，8）。分别获得了当量的 a/a'非对映异构体混合物。此外，5a 和 5a'可以分离。[RhCl(NBD)]2与外消旋 PPh2(CH(Ph)CH2CHO)和氮供体反应，提供了降蒈基（Ntyl）衍生物[RhCl(NN)(Ntyl)(PPh2CH(Ph)CH2CO)]（NN = 苯，9 和 bipy，10）作为 a/a'=75：25 的非对映异构体混合物。通过使[RhCl(NBD)]2与 PPh2(CH(Ph)CH2CHO)和喹啉-8-甲醛在甲醇中反应，得到膦酸酯配合物[RhCl(Ntyl)(C9H6NCO)(κ2-PPh2CH(Ph)CH2CO(OCH3)] 11。最初的等摩尔混合物的两种非对映异构体很容易转化为单一的非对映异构体，这通过 DFT 计算被发现是热力学上最稳定的。此外，还报道了 cis-Cl-2b、5a、7a、10a 和 11 的单晶 X 射线衍射分析。
