Reactions of Diacetylene Ligands with Trinuclear Clusters; Cyclization of Diynes with beta-amino moieties on the surface of H2Os3(CO)10

Summary, in English

Reactions of [H2Os3(CO)10] with the substituted diynes R-C2-C2-R' (1, R = Ph, R' = CH2NHPh; 2, R = Ph, R' = CH2NHCH2Ph; 3, R = R' = CH2NHPh) afford the clusters [HOs3(CO)10(L)] (L = {-1:2-PhCH2C(H)=C-C(H)=C-NPh} (4), {-1:2-PhCH2C(H)=C-C(H)=C-NCH2Ph} (5), and {-1:1-CH3CC=C-C(H)=C(H)-NPh} (6), which have been characterized by single-crystal X-ray diffraction analyses as well as by various spectroscopic methods. In clusters 4-6, the starting diynes 1-3 have been rearranged to form substituted pyrrolyl rings which bridge two osmium atoms in 1:2- (4, 5) or 1:1- (6) coordination modes depending on the nature of substituents in 1-3. A possible reaction pathway for the diyne cyclization reactions that yield 4-6 involves initial transfer of a hydride onto a coordinated diyne followed by a series of 1,3-shifts and subsequent nucleophilic attack of the nitrogen on the third carbon atom of the diyne system to afford the five-membered pyrrolyl ring. Cluster 6 and its previously characterized furanyl analogue [HOs3(CO)10{-1:1-(OCHCHCC)-C-CH3)}] (7) undergo facile thermal transformation accompanied by the loss of a CO ligand to give the clusters [HOs3(CO)9{3,3-CH3CC=C-C(H)=C(H)-NPh}] (8) and [HOs3(CO)9{3,3-(OCH=CHC=CCCH3)}] (9). In both 8 and 9, single-crystal X-ray analysis revealed the presence of pentagonal pyramid cluster cores containing three osmium and three carbon atoms.

• Author: Sergey Tunik; Valerii Khripun; Irina Balova; Ebbe Nordlander; Matti Haukka; Tapani Pakkanen; Paul Raithby
• Department/s: Department of Chemistry
• Publishing year: 2001
• Language: English
• Pages: 3854-3863
• Publication/Series: Organometallics
• Volume: 20
• Issue: 18
• Links: http://dx.doi.org/10.1021/om010400a
• Document type: Journal article
• Publisher: The American Chemical Society (ACS)
• Topic: Inorganic Chemistry
• Status: Published
• ISBN/ISSN/Other: ISSN: 1520-6041