14-Hydroxylation of Opiates:  Catalytic Direct Autoxidation of Codeinone to 14-Hydroxycodeinone

Zhang, Qibo; Rich, Joseph O.; Cotterill, Ian C.; Pantaleone, David P.; Michels, Peter C.

doi:10.1021/ja051682z

Cited by 22 publications

(21 citation statements)

References 18 publications

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“…A mechanism for this oxidation through enolization and oneelectron transfer to adventitious Co III is suggested by recent literature. [31] In summary of the results described in this section, it is clear that the pyridone nucleus bearing tethered C À C triple bonds is a relatively effective cocyclization partner with alkynes, but the reaction displays a subtle divergence in its outcome, which seemingly is strongly dependent on the length of the tether linking the nitrogen atom with the proximal triple bond. In accord with previous findings in the pyrimidine series, [7] tethering one or both of the alkyne units causes an inversion of the stereochemistry of the resulting cobalt complex to anti.…”

mentioning

confidence: 87%

Cobalt‐Mediated [2+2+2] Cycloaddition versus CH and NH Activation of Pyridones and Pyrazinones with Alkynes: An Experimental Study

Aubert

Betschmann

Eichberg

et al. 2007

Chemistry A European J

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The reactivity of a range of pyridone and pyrazinone derivatives towards alkynes in the presence of cyclopentadienylcobaltbis(ethene) has been investigated. Depending on the nature of the substrates, [2+2+2]- or [2+2] cycloaddition, C-H, or N-H activation may occur. In the case of pyridones, the first three predominated with N-protected derivatives, whereas substrates containing N-H bonds followed an N-H activation pathway. The [2+2+2] cycloaddition of an N-butynylisoquinolone was applied successfully to the total synthesis of anhydrolycorinone. Pyrazinone substrates showed similar patterns of reactivity.

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mentioning

confidence: 87%

Cobalt‐Mediated [2+2+2] Cycloaddition versus CH and NH Activation of Pyridones and Pyrazinones with Alkynes: An Experimental Study

Aubert

Betschmann

Eichberg

et al. 2007

Chemistry A European J

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“…[9] A related aluminum-free cationic alkyl yttrium species bearing silylene-linked cyclopentadienylphosphido ligands shows exclusive 3,4-selectivity for the polymerization of isoprene, while a cationic alkyl yttrium species bearing the C 5 Me 4 SiMe 3 ligand yields a mixture of 3,4-and 1,4-polyisoprenes under similar conditions. [10] The search for more selective, simpler, and better-controlled catalyst systems for the cis-1,4 polymerization and copolymerization of isoprene and butadiene is therefore of interest and importance.…”

mentioning

confidence: 99%

“…[10,11] Although late transition-metal complexes containing PNP ligands have received much interest recently, [12] studies on PNP-ligated rare-earth metal complexes remain very limited. [13] Analogous to the synthesis of half-sandwich rare-earth metal bis(alkyl) complexes, [10,11] the acid/base reaction of the tris-(alkyl) complexes [Ln(CH 2 SiMe 3 ) 3 (thf) 2 ] with one equivalent of (2-(Ph 2 P)C 6 H 4 ) 2 NH…”

mentioning

confidence: 99%

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Cationic Alkyl Rare‐Earth Metal Complexes Bearing an Ancillary Bis(phosphinophenyl)amido Ligand: A Catalytic System for Living cis‐1,4‐Polymerization and Copolymerization of Isoprene and Butadiene

et al. 2007

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The creation of new polymer materials with well-controlled microstructures and desired properties relies on the development of new generations of polymerization catalysts. cis-1,4-Regulated polyisoprene (PIP) and polybutadiene (PBD) are among the most important elastomers used for tires and other elastic materials. As the demand for high-performance synthetic rubbers has increased, the development of highquality elastomers by polymerization of isoprene and butadiene has grown in importance. In addition, the limited supply of natural rubber has promoted the need for improved synthetic polyisoprene. [1] To date a variety of catalyst systems have been reported for the polymerization of butadiene and isoprene, among which catalysts based on rare-earth metals have attracted special attention because of their high activity and high cis-1,4 selectivity.[2] The catalysts utilized industrially for the cis-1,4 polymerization of butadiene and isoprene are heterogeneous Ziegler-Natta-type multicomponent systems that consist typically of a rare-earth metal (e.g., Nd) carboxylate, ethylaluminum chloride, and isobutylaluminum hydride. [2a-c] To mimic and improve the industry catalyst systems, and to gain a better understanding of the mechanistic aspects of these heterogeneous catalysts, various discrete rare-earth metal carboxylate and alkoxide complexes as well as rareearth metal/aluminum heterometallic alkyl complexes have been investigated.[3] Some of these molecular systems show very high cis-1,4 selectivity (up to 99 %) when combined with a chloride additive, such as Et 2 AlCl. However, similar to the heterogeneous industrial catalysts, such binary or ternary catalyst systems generally lack "livingness" and yield polymers with rather broad molecular-weight distributions. On the other hand, lanthanide metallocene-based catalyst sys- [4b] have been found to afford polymers with both high cis-1,4 selectivity (up to 99 %) and a narrow molecularweight distribution, or "livingness" (M w /M n = 1.20-1.23), in the polymerization of butadiene under appropriate conditions, [4] however, the polymerization of isoprene has not been achieved in a "living" fashion with such catalyst systems.[4f]Very recently, the combination of a Nd/Mg heterotrimetallic allyl complex with methylaluminoxane (MAO) was reported to show both high cis-1,4 selectivity (95-99 %) and a relatively narrow molecular-weight distribution (M w /M n = 1.3-1.7) for the polymerization of isoprene. [5,6] A common feature in the reported catalyst systems is that they all require an aluminum additive, such as AlR 2 Cl, AlR 3 , or MAO, to show high activity and high cis-1,4 selectivity, which makes it difficult to identify the true catalytic species and to understand the mechanistic aspects of the polymerization process. [2][3][4][5][6][7][8] Recently, cationic methylyttrium species, such as [YMe 2Àn (solv) x ] n+1 (n = 0, 1; solv = solvent), have been reported to show activity for the polymerization of butadiene and isoprene in the absence of an aluminum additive, but ...

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“…Among these, C14-hydroxylation is of particular importance, since it has been shown to improve the pharmacological properties of morphine alkaloids (Lister et al 1999;Zhang et al 2005). Generally, 14-hydroxylated opioids are synthesized using thebaine as the starting material.…”

Section: Resultsmentioning

confidence: 99%

Bioconversion of codeine to semi-synthetic opiate derivatives by the cyanobacterium Nostoc muscorum

Niknam

Faramarzi

Abdi

et al. 2009

World J Microbiol Biotechnol

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Very limited studies have been done to investigate the algal biotransformation of codeine to its opioid derivatives. On the other hand, microalgae have been recently introduced as potential tools for green synthesis of various organic compounds. In the present work, the capability of biotransformation of codeine by a locally isolate strain of cyanobacterium, Nostoc muscorum, was evaluated. Incubation of the whole cells of Nostoc muscorum with codeine (I) under continuous light photoregime of 60 lmol photons/m 2 s at 25°C for 5 days gave rise to four transformation products. The bioproducts were separated by gas chromatography and identified as 6-acetylcodeine (II), oxycodone (III), norcodeine (IV), morphine (V) and based on their mass spectra. Observed modifications included O-demethylation, N-demethylation, C6-acetylation, C14-hydroxilation, D 7 -reduction, and C6-oxidation. The ability of N. muscorum to convert codeine to oxycodone (III) represents an uncommon pattern of codeine metabolism in microorganisms that may be of industrial importance.

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14-Hydroxylation of Opiates: Catalytic Direct Autoxidation of Codeinone to 14-Hydroxycodeinone

Cited by 22 publications

References 18 publications

Cobalt‐Mediated [2+2+2] Cycloaddition versus CH and NH Activation of Pyridones and Pyrazinones with Alkynes: An Experimental Study

Cobalt‐Mediated [2+2+2] Cycloaddition versus CH and NH Activation of Pyridones and Pyrazinones with Alkynes: An Experimental Study

Cationic Alkyl Rare‐Earth Metal Complexes Bearing an Ancillary Bis(phosphinophenyl)amido Ligand: A Catalytic System for Living cis‐1,4‐Polymerization and Copolymerization of Isoprene and Butadiene

Bioconversion of codeine to semi-synthetic opiate derivatives by the cyanobacterium Nostoc muscorum

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