Transition metal-alkenyl complexes [M–(CH2)nCHCH2, n≥2]: Synthesis, structure, reactivity and applications

Reactivity and mechanism in the ring-opening of cyclopropylmethylplatinum(IV) complexes

“…The transition metal may play a direct role in the ring-opening step, but it is also well known that cyclopropylmethyl to butenyl isomerisation may occur within the organic free radicals, cations or anions [3][4][5][6]. Some insights into the mechanisms have been gained by study of stoichiometric reactions, but there are still surprisingly few known examples of thermally stable transition metal complexes with cyclopropylmethyl or cyclobutylmethyl ligands to act as model compounds [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Cyclopropylmethyl complexes are often generated by insertion of methylenecyclopropane [1,2,[7][8][9][10][11][12][13] while cyclobutylmethyl complexes have usually been prepared by transmetalation [16][17][18].…”

Synthesis and reactivity of platinacycloalkanes

“…In the present paper, we report the synthesis of new medium to large ring platinacycles of the type L 2 M(CH 2 ) n (where n ¼ 8, 18, 20; L 2 ¼ dppp or dppe) from their bis(1-alkenyl) precursors, [19] i.e. with up to a 21-membered ring compound by this route (Scheme 1).…”

Alkenyl complexes of platinum group metals: a platform for diverse reactivity patterns

“…Metal‐alkyls, alkenyls and metallacycloalkanes are very well documented species among the classical organometallic compounds, and they play a vital role in many synthetic and catalytic reactions . Ever since the preparation of the first metal‐alkenyl complex reported by Green and Smith, valuable insights into the mechanistic details of these reactions have been elucidated, including both thermodynamic and kinetic aspects .…”

“…Ever since the preparation of the first metal‐alkenyl complex reported by Green and Smith, valuable insights into the mechanistic details of these reactions have been elucidated, including both thermodynamic and kinetic aspects . The chemistry of metal‐alkenyls has experienced a notable development during the last few years, in part due to their involvement in different catalytic processes and their applications in organic synthesis, some of which can be found in the currently available literature . M‐alkenyl complexes have been postulated as key intermediates in the Fischer–Tropsch process and ethylene oligomerization reactions including the generation of thin platinum films for micro‐electronic and catalytic applications through the chemical vapor deposition (CVD) method .…”

“…Although it might be anticipated that metal‐alkenyls should display similar properties to open‐chain dialkyl transition metal complexes or metallacycles, they exhibit high reactivity due to the involvement of an olefinic double bond. The chemical properties are rather different from other known metal complexes of substituted alkyl or aryl complexes . Since then, the chemistry of metal‐alkenyls of platinum group metals (PGM) has been a current research topic in our laboratories, and a review on the exciting chemistry of metal‐alkenyls would be worthwhile.…”