ISSN:
0009-2940
Keywords:
Thiophosphinitomanganese complexes / Cyclocotrimerization / Thiophenes / Furans / Phospholes
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Metal-Containing Heterocycles: Preparation, Properties, Reactions. LXIX It. - Independent Mechanisms of the Cyclocotrimerization of Thiophosphinito Manganese Complexes with Alkynes. - An Easy Access to Five-Membered HeterocyclesIn solution the dimeric thiophosphinitomanganese complexes (1), Et (2), nPr(3)] are in equilibrium with the monomeric species . For R1= iPr (7) and CY (8) the complexes are kinetically stabilized. In THF 4 - 8 react with different activated alkynes R2C≡CR2 to from the S-isomeric five-membered heterocycles (11a, b, e-i). With additional alkynes R2C≡CR2, 11a, b, e-i are trans membered heterocycles (10g to i are also obtained. In n-hexane, the P-isomeric seven membered thiaphosphamanganacycloheptadiens (14g-K) are formed in a [2 + 2 + 2) cycloaddition of 7, 8 to two molecules of R2C≡CR2. at elevated temperatures 14g-K eliminate CO with formation of the bicyclic compounds 12g-k. the action of MeC≡CCO2Me on 8 affords the seven-membered ring 15 in a regiospecific [2 + 2 +2] cycloaddition. 12a-d, h, i and 15 are starting compounds for easy access to the different substituted thiophenes 17, 18a-d, furans 19 h, i, and hte phosphole complexes 20a, b, h, i.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19901230422
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