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1. Hydrogen Bond‐Assisted Fluoride Binding by a Stiborane

   https://doi.org/10.1002/zaac.202200098  

   Karimi, M.; Gabbaï, F. P. (May 2022, Zeitschrift für anorganische und allgemeine Chemie)

   Abstract To augment the fluoride binding ability of Lewis acidic stiboranes, we have synthesized and characterized a Sb^Vderivative (PhSbF₂((o‐(NH(2,6‐C₆H₃F₂)C₆H₄)₂,3) featuring diarylamine groups installed in proximity to the antimony center and poised to engage Sb‐bound fluoride anions in hydrogen bonding interactions. A competition experiment between3and Ph₃SbF₂(4) along with calculations show that the fluoride ion affinity of3is superior to that of4. 

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2. A cationic gold-fluorenyl complex with a dative Au → C ⁺ bond: synthesis, structure, and carbophilic reactivity

   https://doi.org/10.1039/D2CC05436A  

   Litle, Elishua D.; Gabbaï, François P. (January 2023, Chemical Communications)

   Aiming to study the interaction of gold with the highly Lewis acidic fluorenyl cation, we synthesised ( o -[Ph 2 P(C 6 H 4 )Flu)AuCl(tht)][BF 4 ] ([2][BF 4 ]) and ( o -Ph 2 P(C 6 H 4 )Flu)AuCl 2 (3) (Flu = 9-fluorenyl) and found that the latter could be converted into [( o -Ph 2 P(C 6 H 4 )Flu)AuCl] + ([4] + ) upon treatment with NaBArF 24 (BArF 24 = B(3,5-C 6 H 3 (CF 3 ) 2 ) 4 ). [4] + , which has been isolated as a chloride-bridged dimer, readily catalyses the cycloisomerisation of 2-allyl-2-(2-propynyl)malonate. Computational results show that [4] + possesses a strong Au → C + bond and readily activates enynes. 

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3. Redox-controlled chalcogen and pnictogen bonding: the case of a sulfonium/stibonium dication as a preanionophore for chloride anion transport

   https://doi.org/10.1039/D0SC04417B  

   Park, Gyeongjin; Gabbaï, François P. (September 2020, Chemical Science)

   null (Ed.)

   Our interest in the chemistry of tunable chalcogen and pnictogen bond donors as Lewis acidic platforms for the complexation and transport of anions has led us to investigate examples of such compounds that can be activated by redox events. Here, we describe the synthesis of [ o -MePhS(C 6 H 4 )SbPh 3 ] 2+ ([ 3 ] 2+ ) and [ o -MePhS(C 6 H 4 )Sb( p -Tol) 3 ] 2+ ([ 4 ] 2+ ), two dicationic stibonium/sulfonium bifunctional Lewis acids which were obtained by methylation of the phenylthioether derivatives [ o -PhS(C 6 H 4 )SbPh 3 ] + ([ 1 ] + ) and [ o -PhS(C 6 H 4 )Sb( p -Tol) 3 ] + ([ 2 ] + ), respectively. An evaluation of the chloride anion transport properties of these derivatives using chloride-loaded POPC unilamellar vesicles shows that the activity of the monocations [ 1 ] + and [ 2 ] + greatly exceeds that of the dications [ 3 ] 2+ and [ 4 ] 2+ , a phenomenon that we assign to the higher lipophilicity of the monocationic compounds. Harnessing this large transport activity differential, we show that [ 4 ] 2+ can be used as a prechloridophore that is readily activated by reduction of the sulfonium moiety. Indeed, [ 4 ] 2+ reacts with GSH to afford [ 2 ] + as an active transporter. This activation, which has been monitored in aqueous solution, can also be carried out in situ , in the presence of the chloride-loaded POPC unilamellar vesicles. 

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4. 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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5. P-Alkynyl functionalized benzazaphospholes as transmetalating agents

   https://doi.org/10.1039/d0dt01367f  

   Zhou, Daniel Y.; Miura-Akagi, Preston M.; McCarty, Sierra M.; Guiles, Celeste H.; O'Donnell, Timothy J.; Yoshida, Wesley Y.; Krause, Colleen E.; Rheingold, Arnold L.; Hughes, Russell P.; Cain, Matthew F. (January 2021, Dalton Transactions)

   null (Ed.)

   Exposure of 10π-electron benzazaphosphole 1 to HCl, followed by nucleophilic substitution with the Grignard reagent BrMgCCPh afforded alkynyl functionalized 3 featuring an exocyclic –CC–Ph group with an elongated P–C bond (1.7932(19) Å). Stoichiometric experiments revealed that treatment of trans -Pd(PEt 3 ) 2 (Ar)( i ) (Ar = p -Me ( C ) or p -F ( D )) with 3 generated trans -Pd(PEt 3 ) 2 (Ar)(CCPh) (Ar = p -Me ( E ) or p -F ( F )), 5 , which is the result of ligand exchange between P–I byproduct 4 and C/D , and the reductively eliminated product (Ar–CC–Ph). Cyclic voltammetry studies showed and independent investigations confirmed 4 is also susceptible to redox processes including bimetallic oxidative addition to Pd(0) to give Pd( i ) dimer 6-Pd2-(P(t-Bu)3)2 and reduction to diphosphine 7 . During catalysis, we hypothesized that this unwanted reactivity could be circumvented by employing a source of fluoride as an additive. This was demonstrated by conducting a Sonogashira-type reaction between 1-iodotoluene and 3 in the presence of 10 mol% Na 2 PdCl 4 , 20 mol% P( t -Bu)Cy 2 , and 5 equiv. of tetramethylammonium fluoride (TMAF), resulting in turnover and the isolation of Ph–CC–( o -Tol) as the major product. 

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