Dreifach‐verbrückte Diphosphane mit von innen nach außen invertierender Konfiguration

Stollenz, Michael; Barbasiewicz, Michał; Nawara‐Hultzsch, Agnieszka J.; Fiedler, Tobias; Laddusaw, Ryan M.; Bhuvanesh, Nattamai; Gladysz, J. A.

doi:10.1002/ange.201100893

Cited by 20 publications

(11 citation statements)

References 31 publications

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“…We have described the syntheses and a limited range of reactions of the in / out isomers of the dibridgehead diphosphine P((CH 2 ) 14 ) 3 P ( 1 ), , which feature 30-membered macrocycles. These molecules have a fascinating ability to turn themselves inside out, which has been termed homeomorphism .…”

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confidence: 69%

Homeomorphic Isomerization as a Design Element in Container Molecules; Binding, Displacement, and Selective Transport of MCl₂ Species (M = Pt, Pd, Ni)

et al. 2017

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The dibridgehead diphosphine ((CH)) P (1) can rapidly turn inside-out (homeomorphic isomerization) to give a mixture of in,in and out,out isomers. The exo directed lone pairs in the latter are able to scavenge Lewis acidic MCl; cagelike adducts of the in,in isomer, trans- Cl(P((CH)) P) (M = 2/Pt, 3/Pd, 4/Ni), then form. The NiCl unit in 4 may be replaced by PtCl or PdCl, but 2 and 3 do not give similar substitutions. U-tubes are charged with CHCl solutions of 1 (lower phase), an aqueous solution of KMCl (charging arm; M = Pt, Pd), and an aqueous solution of excess KCl (receiving arm). The MCl units are then transported to the receiving arm until equilibrium is reached (up to 22 d). When the receiving arm is charged with KCN, transport is much faster (ca. 100 h) and higher KMX equilibrium ratios are obtained (≥96≤4). Analogous experiments with KPtCl/KPdCl mixtures show PdCl transport to be more rapid. A similar diphosphine with longer methylene chains, P((CH))P, is equally effective. No transport occurs in the absence of 1, and other diphosphines or monophosphines assayed give only trace levels.

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confidence: 69%

Homeomorphic Isomerization as a Design Element in Container Molecules; Binding, Displacement, and Selective Transport of MCl₂ Species (M = Pt, Pd, Ni)

et al. 2017

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“…We have sought to better understand the nuances of this process, especially with respect to kinetic and thermodynamic control of geometric isomerism. The dibridgehead diphosphines are themselves capable of dynamic processes, such as “homeomorphic isomerization”, which exchanges exo directed ( out , out ) and endo directed ( in , in ) functionality without any intervening inversions of configuration at phosphorus (Scheme ). However, these phenomena do not play a role in this study.…”

Section: Introductionmentioning

confidence: 99%

Three-Fold Intramolecular Ring Closing Alkene Metatheses of Square Planar Complexes with cis Phosphorus Donor Ligands P(X(CH₂)_mCH═CH₂)₃ (X = −, m = 5–10; X = O, m = 3–5): Syntheses, Structures, and Thermal Properties of Macrocyclic Dibridgehead Diphosphorus Complexes

et al. 2018

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Reactions of cis-PtCl(P((CH) CH═CH)) and Grubbs' first generation catalyst and then hydrogenations afford cis- PtCl(P((CH) ) P) ( cis-2; n = 2 m + 2 = 12 (b), 14 (c), 16 (d), 18 (e), 20 (f), 22 (g); 6-40%), derived from 3-fold interligand metatheses. The phosphite complexes cis-PtCl(P(O(CH) CH═CH)) are similarly converted to cis- PtCl(P(O(CH) O) P) ( cis-5; n* = 8 (a), 10 (b), 12 (c), 10-20%). The substitution products cis- PtPh(P((CH) ) P) ( cis-6c,d) and cis- PtI(P(O(CH)O) P) are prepared using PhZn and NaI, respectively. Crystal structures of cis-2c,d,f, cis-5a,b, and cis-6c show one methylene bridge that roughly lies in the platinum coordination plane and two that are perpendicular. The thermal behavior of the complexes is examined. When the bridges are sufficiently long, they rapidly exchange via an unusual "triple jump rope" motion over the PtX moieties. NMR data establish Δ H, Δ S, and Δ G/Δ G values of 7.8 kcal/mol, -27.9 eu, and 16.1/18.8 kcal/mol for cis-2d, and a Δ G of ≥19.6 kcal/mol for the shorter bridged cis-2c. While cis-2c,g gradually convert to trans-2c,g at 150-185 °C in haloarenes, trans-2c,g give little reaction under analogous conditions, establishing the stability order trans > cis. Similar metathesis/hydrogenation sequences with octahedral complexes containing two cis phosphine ligands, fac-ReX(CO)(P((CH)CH═CH)) (X = Cl, Br), give fac- ReX(CO)( P(CH) CH)((CH))( P(CH) CH) (19-50%), which are derived from a combination of interligand and intraligand metathesis. The relative stabilities of cis/ trans and other types of isomers are probed by combinations of molecular dynamics and DFT calculations.

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“…(3) Is the stability order trans - 2 > cis - 2 maintained? Additional motivation was provided by earlier observations that reactions of trans - 2c , e and excesses of appropriate nucleophiles liberate the dibridgehead diphosphines 3c , e , as shown in Scheme . − These can serve as “container molecules” for the selective transport of PtCl 2 and PdCl 2 away from NiCl 2 . It was thought that diphosphines with larger macrocycles might exhibit complementary selectivities, as well as other interesting chemistry.…”

Section: Introductionmentioning

confidence: 99%

Syntheses, Structures, and Thermal Properties of Gyroscope-like Complexes Consisting of PtCl₂ Rotators Encased in Macrocyclic Dibridgehead Diphosphines P((CH₂)_n)₃P with Extended Methylene Chains (n = 20/22/30) and Isomers Thereof

et al. 2018

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Reactions of P((CH 2 ) m CHCH 2 ) 3 (2.0 equiv; m = 9 (f), 10 (g), 14 (k)) and PtCl 2 in toluene give trans-PtCl 2 (P((CH 2 ) m CHCH 2 ) 3 ) 2 (trans-1f,g,k; 63−49%). Reactions of trans-1f,g with Grubbs first generation catalyst (CH 2 Cl 2 /reflux) followed by hydrogenations (cat. PtO 2 ) afford chromatographically separable gyroscope-like trans-PtCl 2 (P((CH 2 ) n ) 3 P) (trans-2f,g, 3−19%; from interligand metathesis) and trans-PtCl 2 (P((CH 2 ) n−1 CH 2 )-(CH 2 ) n P((CH 2 ) n−1 CH 2 )) (trans-2′f,g, 25−12%; from interand intraligand metathesis), where n = 2m + 2. Under analogous conditions, trans-1k gives only cis-PtCl 2 (P((CH 2 ) 30 ) 3 P) (cis-2k, 39%), but when o-C 6 H 4 Cl 2 solutions are kept at 180 °C, trans-2k forms (quantitative by 31 P NMR; 72% isolated). In contrast, a similar sequence with the Hoveyda−Grubbs second generation catalyst gives only trans-2k (8%). The stability order cis > trans is established for 1g and 2′f,g in CH 2 Cl 2 (61−56:39−44; months at RT), but the opposite is found for 1g and 2′f in toluene (9−7:91−93) or 2′f in o-C 6 H 4 Cl 2 (7:93). Thus, it is proposed that the conversion of trans-1k to cis-2k involves a geometrical isomerization of the educt or an intermediate catalyzed by a species derived from Grubbs catalyst. The crystal structures of trans-2g•THF and cis-2′f,g are determined and analyzed in detail.

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Dreifach‐verbrückte Diphosphane mit von innen nach außen invertierender Konfiguration

Cited by 20 publications

References 31 publications

Homeomorphic Isomerization as a Design Element in Container Molecules; Binding, Displacement, and Selective Transport of MCl₂ Species (M = Pt, Pd, Ni)

Homeomorphic Isomerization as a Design Element in Container Molecules; Binding, Displacement, and Selective Transport of MCl₂ Species (M = Pt, Pd, Ni)

Three-Fold Intramolecular Ring Closing Alkene Metatheses of Square Planar Complexes with cis Phosphorus Donor Ligands P(X(CH₂)_mCH═CH₂)₃ (X = −, m = 5–10; X = O, m = 3–5): Syntheses, Structures, and Thermal Properties of Macrocyclic Dibridgehead Diphosphorus Complexes

Syntheses, Structures, and Thermal Properties of Gyroscope-like Complexes Consisting of PtCl₂ Rotators Encased in Macrocyclic Dibridgehead Diphosphines P((CH₂)_n)₃P with Extended Methylene Chains (n = 20/22/30) and Isomers Thereof

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Dreifach‐verbrückte Diphosphane mit von innen nach außen invertierender Konfiguration

Cited by 20 publications

References 31 publications

Homeomorphic Isomerization as a Design Element in Container Molecules; Binding, Displacement, and Selective Transport of MCl2 Species (M = Pt, Pd, Ni)

Homeomorphic Isomerization as a Design Element in Container Molecules; Binding, Displacement, and Selective Transport of MCl2 Species (M = Pt, Pd, Ni)

Three-Fold Intramolecular Ring Closing Alkene Metatheses of Square Planar Complexes with cis Phosphorus Donor Ligands P(X(CH2)mCH═CH2)3 (X = −, m = 5–10; X = O, m = 3–5): Syntheses, Structures, and Thermal Properties of Macrocyclic Dibridgehead Diphosphorus Complexes

Syntheses, Structures, and Thermal Properties of Gyroscope-like Complexes Consisting of PtCl2 Rotators Encased in Macrocyclic Dibridgehead Diphosphines P((CH2)n)3P with Extended Methylene Chains (n = 20/22/30) and Isomers Thereof

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Homeomorphic Isomerization as a Design Element in Container Molecules; Binding, Displacement, and Selective Transport of MCl₂ Species (M = Pt, Pd, Ni)

Homeomorphic Isomerization as a Design Element in Container Molecules; Binding, Displacement, and Selective Transport of MCl₂ Species (M = Pt, Pd, Ni)

Three-Fold Intramolecular Ring Closing Alkene Metatheses of Square Planar Complexes with cis Phosphorus Donor Ligands P(X(CH₂)_mCH═CH₂)₃ (X = −, m = 5–10; X = O, m = 3–5): Syntheses, Structures, and Thermal Properties of Macrocyclic Dibridgehead Diphosphorus Complexes

Syntheses, Structures, and Thermal Properties of Gyroscope-like Complexes Consisting of PtCl₂ Rotators Encased in Macrocyclic Dibridgehead Diphosphines P((CH₂)_n)₃P with Extended Methylene Chains (n = 20/22/30) and Isomers Thereof