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1. Wire like diplatinum, triplatinum, and tetraplatinum complexes featuring X[PtCCCCCCCC] _m PtX segments; iterative syntheses and functionalization for measurements of single molecule properties

   https://doi.org/10.1039/C9DT00870E  

   Zheng, Qinglin; Schneider, Jakob F.; Amini, Hashem; Hampel, Frank; Gladysz, John A. (April 2019, Dalton Transactions)

   Reaction of ( p -tol 3 P) 2 PtCl 2 and Me 3 Sn(CC) 2 SiMe 3 (1 : 1/THF/reflux) gives monosubstituted trans -Cl( p -tol 3 P) 2 Pt(CC) 2 SiMe 3 (63%), which with wet n -Bu 4 N + F − yields trans -Cl( p -tol 3 P) 2 Pt(CC) 2 H ( 2 , 96%). Hay oxidative homocoupling (O 2 /CuCl/TMEDA) gives all- trans -Cl( p -tol 3 P) 2 Pt(CC) 4 Pt(P p -tol 3 ) 2 Cl ( 3 , 68%). Reaction of 3 and Me 3 Sn(CC) 2 SiMe 3 (1 : 1/rt) affords monosubstituted all- trans -Cl( p -tol 3 P) 2 Pt(CC) 4 Pt(P p -tol 3 ) 2 (CC) 2 SiMe 3 (46%), which is converted by a similar desilylation/homocoupling sequence to all- trans -Cl[( p -tol 3 P) 2 Pt(CC) 4 ] 3 Pt(P p -tol 3 ) 2 Cl ( 7 ; 79%). Reaction of ( p -tol 3 P) 2 PtCl 2 and excess H(CC) 2 SiMe 3 (HNEt 2 /cat. CuI) gives trans -Me 3 Si(CC) 2 Pt(P p -tol 3 ) 2 (CC) 2 SiMe 3 (78%), which with wet n -Bu 4 N + F − affords trans -H(CC) 2 Pt(P p -tol 3 ) 2 (CC) 2 H (96%). Hay oxidative cross coupling with 2 (1 : 4) gives all- trans -Cl[( p -tol 3 P) 2 Pt(CC) 4 ] 2 Pt(P p -tol 3 ) 2 Cl ( 10 , 36%) along with homocoupling product 3 (33%). Reaction of 3 and Me 3 Sn(CC) 2 SiMe 3 (1 : 2/rt) yields all- trans -Me 3 Si(CC) 2 ( p -tol 3 P) 2 Pt(CC) 4 Pt(P p -tol 3 ) 2 (CC) 2 SiMe 3 ( 17 , 77%), which with wet n -Bu 4 N + F − gives all- trans -H(CC) 2 ( p -tol 3 P) 2 Pt(CC) 4 Pt(P p -tol 3 ) 2 (CC) 2 H (96%). Reaction of 3 and excess Me 3 P gives all- trans -Cl(Me 3 P) 2 Pt(CC) 4 Pt(PMe 3 ) 2 Cl ( 4 , 86%). A model reaction of trans -( p -tol)( p -tol 3 P) 2 PtCl and KSAc yields trans -( p -tol)( p -tol 3 P) 2 PtSAc ( 12 , 75%). Similar reactions of 3 , 7 , 10 , and 4 give all- trans -AcS[(R 3 P) 2 Pt(CC) 4 ] n Pt(PR 3 ) 2 SAc (76–91%). The crystal structures of 3 , 17 , and 12 are determined. The first exhibits a chlorine–chlorine distance of 17.42 Å; those in 10 and 7 are estimated as 30.3 Å and 43.1 Å. 

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2. H ₂ evolution from H ₂ O via O–H oxidative addition across a 9,10-diboraanthracene

   https://doi.org/10.1039/D0CC05261B  

   Taylor, Jordan W.; Harman, W. Hill (November 2020, Chemical Communications)

   null (Ed.)

   The water reactivity of the boroauride complex ([Au(B 2 P 2 )][K(18-c-6)]; (B 2 P 2 , 9,10-bis(2-(diisopropylphosphino)-phenyl)-9,10-dihydroboranthrene) and its corresponding two-electron oxidized complex, Au(B 2 P 2 )Cl, are presented. Au(B 2 P 2 )Cl is tolerant to H 2 O and forms the hydroxide complex Au(B 2 P 2 )OH in the presence of H 2 O and triethylamine. [Au(B 2 P 2 )]Cl and [Au(B 2 P 2 )]OH are poor Lewis acids as judged by the Gutmann–Becket method, with [Au(B 2 P 2 )]OH displaying facile hydroxide exchange between B atoms of the DBA ring as evidenced by variable temperature NMR spectroscopy. The reduced boroauride complex [Au(B 2 P 2 )] − reacts with 1 equivalent of H 2 O to produce a hydride/hydroxide product, [Au(B 2 P 2 )(H)(OH)] − , that rapidly evolves H 2 upon further H 2 O reaction to yield the dihydroxide compound, [Au(B 2 P 2 )(OH) 2 ] − . [Au(B 2 P 2 )]Cl can be regenerated from [Au(B 2 P 2 )(OH) 2 ] − via HCl·Et 2 O, providing a synthetic cycle for H 2 evolution from H 2 O enabled by O–H oxidative addition at a diboraanthracene unit. 

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3. Delocalization tunable by ligand substitution in [L ₂ Al] ⁿ⁻ complexes highlights a mechanism for strong electronic coupling

   https://doi.org/10.1039/D0SC02812F  

   Arnold, Amela; Sherbow, Tobias J.; Bohanon, Amanda M.; Sayler, Richard I.; Britt, R. David; Smith, Allison M.; Fettinger, James C.; Berben, Louise A. (January 2021, Chemical Science)

   null (Ed.)

   Ligand-based mixed valent (MV) complexes of Al( iii ) incorporating electron donating (ED) and electron withdrawing (EW) substituents on bis(imino)pyridine ligands (I 2 P) have been prepared. The MV states containing EW groups are both assigned as Class II/III, and those with ED functional groups are Class III and Class II/III in the (I 2 P − )(I 2 P 2− )Al and [(I 2 P 2− )(I 2 P 3− )Al] 2− charge states, respectively. No abrupt changes in delocalization are observed with ED and EW groups and from this we infer that ligand and metal valence p-orbitals are well-matched in energy and the absence of LMCT and MLCT bands supports the delocalized electronic structures. The MV ligand charge states (I 2 P − )(I 2 P 2− )Al and [(I 2 P 2− )(I 2 P 3− )Al] 2− show intervalence charge transfer (IVCT) transitions in the regions 6850–7740 and 7410–9780 cm −1 , respectively. Alkali metal cations in solution had no effect on the IVCT bands of [(I 2 P 2− )(I 2 P 3− )Al] 2− complexes containing –PhNMe 2 or –PhF 5 substituents. Minor localization of charge in [(I 2 P 2− )(I 2 P 3− )Al] 2− was observed when –PhOMe substituents are included. 

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4. POCOP-type cobalt and nickel pincer complexes bearing an appended phosphinite group

   https://doi.org/10.1139/cjc-2020-0137  

   Li, Yingze; Krause, Jeanette A.; Guan, Hairong (April 2021, Canadian Journal of Chemistry)

   The reaction of 1,3,5-( i Pr 2 PO) 3 C 6 H 3 with Co 2 (CO) 8 leads to the isolation of a POCOP-type mononuclear pincer complex {κ P ,κ C ,κ P -2,4,6-( i Pr 2 PO) 3 C 6 H 2 }Co(CO) 2 (1) or a tetranuclear species {κ P -{κ P ,κ C ,κ P -2,4,6-( i Pr 2 PO) 3 C 6 H 2 }Co(CO) 2 } 2 Co 2 (CO) 6 (2), depending on the ligand to cobalt ratio employed. The latter compound can be an impurity during the synthesis of {2,6-( i Pr 2 PO) 2 -4-Me 2 N-C 6 H 2 }Co(CO) 2 , when the ligand precursor 5-(dimethylamino)resorcinol is contaminated with phloroglucinol due to incomplete monoamination. Similarly, the reaction of 1,3,5-( i Pr 2 PO) 3 C 6 H 3 with NiCl 2 in the presence of 4-dimethylaminopyridine provides {κ P ,κ C ,κ P -2,4,6-( i Pr 2 PO) 3 C 6 H 2 }NiCl (3) bearing an appended phosphinite group. Structures 1–3 have been studied by X-ray crystallography. 

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5. En route to diplatinum polyynediyl complexes trans,trans-(Ar)(R3P)2Pt(C≡C)nPt(PR3)2(Ar): Untold tales, including end-group strategies

   https://doi.org/10.1351/pac200880030459  

   Stahl, Jürgen; Bohling, James C.; Peters, Thomas B.; de Quadras, Laura; Gladysz, John A. (January 2008, Pure and Applied Chemistry)

   Reactions of {(C 6 F 5 )Pt[S(CH 2 CH 2 -) 2 ](μ-Cl)} 2 and R 3 P yield the bis(phosphine) species trans -(C 6 F 5 )(R 3 P) 2 PtCl [R = Et ( Pt'Cl ), Ph, ( p -CF 3 C 6 H 4 ) 3 P; 88-81 %]. Additions of Pt'Cl and H(C≡C) n H ( n = 1, 2; HNEt 2 , 20 mol % CuI) give Pt'C 2 H (37 %, plus Pt'I , 16 %) and Pt'C 4 H (88 %). Homocoupling of Pt'C 4 H under Hay conditions (O 2 , CuCl, TMEDA, acetone) gives Pt'C 8 Pt' (85 %), but Pt'C 2 H affords only traces of Pt'C 4 Pt' . However, condensation of Pt'C 4 H and Pt'Cl (HNEt 2 , 20 mol % CuI) yields Pt'C 4 Pt' (97 %). Hay heterocouplings of Pt'C 4 H or trans -( p -tol)(Ph 3 P) 2 Pt(C≡C) 2 H ( Pt*C 4 H ) and excess HC≡CSiEt 3 give Pt'C 6 SiEt 3 (76 %) or Pt*C 6 SiEt 3 (89 %). The latter and wet n -Bu 4 N + F - react to yield labile Pt*C 6 H (60 %). Hay homocouplings of Pt*C 4 H and Pt*C 6 H give Pt*C 8 Pt* (64 %) and Pt*C 12 Pt* (64 %). Reaction of trans -(C 6 F 5 )( p -tol 3 P) 2 PtCl ( PtCl ) and HC≡CH (HNEt 2 , 20 mol % CuI) yields only traces of PtC 2 H . However, an analogous reaction with HC≡CSiMe 3 gives PtC 2 SiMe 3 (75 %), which upon treatment with silica yields PtC 2 H (77 %). An analogous coupling of trans -(C 6 F 5 )(Ph 3 P) 2 PtCl with H(C≡C) 2 H gives trans -(C 6 F 5 )(Ph 3 P) 2 Pt(C≡C) 2 H (34 %). Advantages and disadvantages of the various trans -(Ar)(R 3 P) 2 Pt end-groups are analyzed. 

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