Organometallic catalysis: some contributions to organic synthesis

Abstract

Recebido em 27/5/02; aceito em 28/8/02In the present paper some general aspects of metal complex catalysis and its applications for oxyfunctionalization of various olefins, including naturally occurring ones, via selective oxidation, hydroformylation and alkoxycarbonylation are discussed.

Allylic chlorination of terpenic olefins using a combination of MoCl5 and NaOCl

“…Among the Mo compounds studied, MoCl 5 appears the most suitable (entry 3). MoO 3 gives good yield but only after a long reaction time (entry 7). In order to confirm the low activity of MoO 3 , other terpenes were checked, such as carvone and limonene with MoO 3 /NaOCl (0.5 equiv.…”

“…[1][2][3][4] Previously, we have reported that allylic amines, alcohols, ketones and alkoxycarbonyl derivatives can be obtained in good yields by the metal complex catalyzed amination, oxidation and alkoxycarbonylation of some monoterpenes. [5][6][7] Chlorination represents a valuable pathway to produce versatile starting materials that are widely used in synthetic organic chemistry.…”

Topical and prospective processes of acetoxylation

“…Detailed characterization of the acetoxylation catalyst can be found in literature 18,19 . However, the general information about the catalysts applied for the acetoxylation should be briefly presented.…”

“…Complexes of Cu(II), Fe(II), heteropoly acids and benzoquinone are commonly used as reversible oxidants in these systems. The role of the reoxidant has been described in detail in the literature 18 . It follows from literature that palladium can be applied as the catalyst in the form of the Pd-561 giant clusters 19 .…”

Rhodium catalyzed hydroformylation of monoterpenes containing a sterically encumbered trisubstituted endocyclic double bond under mild conditions

“…A number of their functionalized derivatives have olfactory and biological activity, and can be interesting for the pharmaceutical and fragrance industries. [1][2][3] The rhodium catalyzed hydroformylation of special olefins represents a versatile and one of the least expensive synthetic pathways to aldehydes in the fine chemicals industry. In recent years, we have been systematically studying the hydroformylation of various monoterpenes, such as myrcene, limonene, b-pinene, and camphene [4][5][6][7][8][9][10].…”