Une methode simple de liberation des ligands organiques de leurs complexes de fer carbonyle.

Synthetic applications of cationic iron and cobalt carbonyl complexes

“…37 The advantage here is that the reaction conditions are mild and thus compatible with a number of functional groups, although the reaction times can be long in some cases. The use of hydrogen peroxide in basic solution is a more rapid method, 38 and cerium(IV) ammonium nitrate can also be applied, 39 although the latter reagent is more commonly used for the decomplexation of alkynes from cobalt carbonyl complexes. Alternative methods involve the use of copper(II) chloride, 40 iron(III) chloride, 41 or pyridinium chlorochromate.…”

Monoterpenoids

“…The known compound vomifoliol (374) has been extracted from Magnolia stellata Maxim.366 4-Hydroxy-P-damascone (375) is a new natural product from Virginia tobacco.367 It can be produced in uitro, together with the enone (376), by exposing an aqueous solution of P-damascone (377) to air and light for six months. The new glucoside melasmoside (378) has been obtained from the roots of Melasma a r~e n s e .~~~ A number of derivatives of P-ionone have been synthesized and tested for antifungal and antimicrobial activity, the most potent being the ketone (379).…”

“…The most stable compound in this series is [388; M = Fe(CO),], whose structure was determined by X-ray analysis.373 These carbonyl complexes return the organic ligand if they are treated with alkaline H202. 374 No epoxidation of the enone system occurs. The+ reaction of P-ionone (383) with the ylide from Ph3P[CH2I3NMe2 leads to the expected product (389).375 An asymmetric synthesis of both enantiomers of (390) has been reported.376…”

Carotenoids and polyterpenoids

“…Relatively simple structural variations for which syntheses are described include compounds with bulky substituent groups at C-4, e.g. 4-butylretinal (2Ol),lo3 the acetylenic 7,8-didehydroretinal (207) and its 5-demethyl-and 1,1,5-tridemethyl-analogues [( 208) and (2O9)],lo4 and the 1,1,5tridemethyl-( 202),'05 5-demethyl-, 9-demethyl-, 13-demethyl-, and 9,13-didemethyl-retinals ( 203)- (206). O6 A new method for addition of deprotonated ketimines (210) to aldehydes and ketones has been used to prepare the methyl-substituted intermediates (21 1) and ( 212) from p-ionone and P-ionylideneacetaldehyde.…”