ISSN:
0009-2940
Keywords:
Heteroaldehyde complexes / [4 + 2] Cycloaddition, stereoselective / Thiacycles / Selenacycles
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
[4 + 21 Cycloadditions with Transition-Metal-Coordinated Heteroalkenes: The Influence of the Coordination on the Stereoselectivity of the CycloadditonPentacarbonyl(thiobenzaldehyde), -(selenobenzaldehyde), and -(diphenyl selenoketone) complexes (CO)5M[X = C(Ph)R] [R = H: M = W, X = S (1a), Se (1b); M = Cr, X = S (1c), Se (1d); R = Ph: M = W, X = Se (1e)] react with cyclopentadiene (2) and 1,3-cyclohexadiene (4), respectively, by [4 + 2] cycloaddition to give metal-coordinated this- and selenacycles 3 and 5. The additions of 2 and 4 to 1a-d are stereoselective. In contrast to the endo selectivity observed in the reactions of 2 and 4 with uncomplexed thio- and selenoaldehydes, the additions of 2 and 4 to 1a-d are exo selective. However, the reactions of pentamethylcyclopentadiene (6) with 1a,b to form 7 are endo selective. The structures of the main isomer of the addition of 4 to 1c (5c-exo) and of 6 to 1 b (7b-endo) were confirmed by X-ray analyses.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19901230413
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