English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The coordination chemistry of the cyclopropyl-substituted alkenes, bicyclopropylidene (BCP) and methylenecyclopropane (MCP), with platinum was explored. A range of complexes with ŋ²-alkene ligands were synthesised by the displacement of a ligand, typically ethene, from a precursor complex. These complexes are [Pt(L)(P—P)] (L = BCP, MCP; P—P = Ph₂P(CH₂)₃PPh₂, Cy₂P(CH₂)₂PCy₂, ᵗBu₂P(CH₂)₂PᵗBu₂, ᵗBu₂PCH₂(o-C₆H₄)₂PᵗBu₂), [Pt(L)(P—S)] (L = BCP, MCP; P—S = ᵗBu₂PCH₂(o-₆H4)CH₂SᵗBu), [Pt(C₂H4)(L)(PR₃)] (L = BCP, MCP; PR₃ = PPh₃, PCy₃), [Pt(MCP)₂(PR₃)] (PR₃ = PPh₃, PCy₃) and [PtCl₂(L)(L′)] (L = BCP, MCP; L′ = Py, DMSO). These were the first examples of platinum complexes with ŋ²-BCP ligands, and the first bis-MCP Pt complexes.  BCP underwent ring-opening reactions with both Pt(0) and Pt(II) complexes to form the 1,3-diene allylidenecyclopropane (ACP). The first transition metal complexes of ACP [Pt(ACP)(P—P)] (P—P = Ph₂P(CH₂)₃PPh₂, Cy₂P(CH₂)₂PCy₂, ᵗBu₂P(CH₂)₂PᵗBu₂) were synthesised. Some of these complexes rearranged to form ŋ²:σ²-metallacyclopentene complexes, the first instances of the formation of ŋ²:σ²-metallacyclopentene complexes from ŋ²:π-diene complexes. With MCP, the ring-opening reaction only occurred with [₂(COD)], as a result of the anti-Markovnikov addition of Pt–H, generated by the β-hydride elimination of an Et group, across the double-bond. The major products of this reaction were the 1-methylcyclopropyl complexes [Pt(C(CH₂)₂CH₃)Et(COD)] and [Pt(C(CH₂)₂CH₃)₂(COD)], the first examples of such complexes.  Protonation of [Pt(L)(P—P)] resulted in a ring-opening reaction to form both the 2-substituted and 1-methyl allyl complexes, [Pt(ŋ³-CH₂CRCH₂)(P—P)]⁺ (R = ᶜPr, Me; P—P = Ph₂P(CH₂)₃PPh₂, ᵗBu₂PCH₂(o-C₆H₄)CH₂PᵗBu₂) and [Pt(ŋ³-CR₂CHCHMe)(P—P)]⁺ (R = cPr, Me; P—P = Ph₂P(CH₂)₃PPh₂, ᵗBuPCH₂(o-C₆H₄)CH₂PᵗBu₂). The analogous 1-methyl complexes were also formed from [Pt(L)(P—S)], wherein the alkene reacted with a hydride formed by the ortho-metallation of the P—S ligand. Computational models were used to investigate the formation of the allyl structures and it was found that the activation energy had a more significant effect than complex stability on product distributions.  Complexes with β-chloroalkyl ligands [Pt(C(CH₂)₂CR₂Cl)Cl(L)₂] (R = CH₂, H, L = SEt₂, NCᵗBu, Py) were formed by the addition of Pt–Cl across the alkene double bond. Phosphine complexes were formed by the displacement of a ligand from cis–[Pt(C(CH₂)₂CR₂Cl)Cl(Py)₂] (R = CH₂, H). These are the first examples of stable Pt(II) β-haloalkyl complexes. It was found using computational models that the presence of cyclopropyl rings had a stabilising effect on these complexes.

Platinum Complexes of Bicyclopropylidene and Related Ligands