UV irradiation of the cycloheptadienyl complexes [(η5-C7H8R)Cr(CO)3SnPh 3] (1a, R = H; 1b, R = C(Me)S(CH2)3S; 1c, R = CHPh2) or cyclohexadienyl complexes [(η5-C6H6R)Cr(CO)2-(NO)] (7, R = C(Me)S(CH2)3S) and 2 equiv of 2-butyne or 3-hexyne in toluene or n-hexane gave new tricyclic complexes 2, 5, and 8. These complexes arise from sequential [5 + 2] and homo[5 + 2] cycloadditions of two alkyne molecules to the η5-dienyl manifold forming 11-alkylidenetricyclo[5.3.1.04,10]undeca-2,5-diene or tricyclo[5.2.1.04,9]deca-2,5-dien-10-yl ligands, respectively. Heating 2 in acetonitrile gave [Cr(CO)3(CH3CN)3] and the tricyclic organic compounds 3. UV irradiation of 1a and 1-phenyl-1-propyne or 1c and 2-butyne directly gave the organic compounds 4a,b and 5c, 6a,b, respectively, as mixtures of isomers. The adduct resulting from 1a and two molecules of 3-hexyne has been characterized by an X-ray diffraction study.
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry