10.1021/om010800y.s002
Michael C. Janzen
Michael C.
Janzen
Hilary A. Jenkins
Hilary A.
Jenkins
Michael C. Jennings
Michael C.
Jennings
Louis M. Rendina
Louis M.
Rendina
Richard J. Puddephatt
Richard J.
Puddephatt
Ring Expansion and Contraction in Reactions of an
Alkyne with Stannylplatinum(IV) Metallacycles:
Formation of an Alkyl(alkenyl)(alkynyl)platinum(IV)
Complex
American Chemical Society
2002
PtMe 2
electrophilic alkyne RCCR
bu 2 bpy
metallacycle
CO
ESnMe
Se
SnMe
2002-02-16 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Ring_Expansion_and_Contraction_in_Reactions_of_an_Alkyne_with_Stannylplatinum_IV_Metallacycles_Formation_of_an_Alkyl_alkenyl_alkynyl_platinum_IV_Complex/3767583
The five-membered stannylplatinum(IV) metallacycles [PtMe<sub>2</sub>{SnMe<sub>2</sub>ESnMe<sub>2</sub>E}(bu<sub>2</sub>bpy)],
E = S, Se, Te, bu<sub>2</sub>bpy = 4,4‘-di-<i>tert</i>-butyl-2,2‘-bipyridine, undergo facile ring expansion by
insertion of the electrophilic alkyne RCCR, R = CO<sub>2</sub>Me, into the PtE−Sn bond to yield the
corresponding seven-membered metallacycles [PtMe<sub>2</sub>{SnMe<sub>2</sub>ESnMe<sub>2</sub>CRCRE}(bu<sub>2</sub>bpy)]. The
seven-membered metallacycles slowly eliminate “Me<sub>2</sub>SnE” to give new five-membered metallacycles [PtMe<sub>2</sub>{SnMe<sub>2</sub>CRCRE}(bu<sub>2</sub>bpy)]. When E = Se, reaction with excess RCCR gives
the complex [PtMe<sub>2</sub>(CRCRH)(CCR)(bu<sub>2</sub>bpy)], which contains alkyl, alkenyl, and alkynyl
functionalities in the same molecule. In the presence of excess RCCR and [(Me<sub>2</sub>SnSe)<sub>3</sub>], the
products Se(<i>Z</i>-CRCHR)<sub>2</sub> and the selenole Se(CRCRCRCR) are formed catalytically.