In: Journal of the American Chemical Society, 2010, vol. 132, no. 14, p. 5176–5178
A fully diastereoselective total synthesis of the lycorenine-type Amaryllidaceae alkaloid (±)-clivonine is reported via a route that employs for the first time a biomimetic ring-switch from a lycorine-type progenitor, thereby corroborating experimentally the biogenetic hypothesis first expounded for these compounds by Barton in 1960.
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In: Chimia, 2009, vol. 63, no. 12, p. 872-873
The author describes his early steps as an independent researcher at the University of Geneva. His interest in synthetic organic photochemistry came from his past non-experience at the Universities of Geneva and Stanford, where he worked mainly on natural product synthesis and transition-metal catalysis.
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In: Journal of Physical Organic Chemistry, 2010, p. -
The acylation reaction occupies a central role in biochemistry and organic synthesis. On the one hand, it is by this very reaction that amino acids successively assemble to form peptides and proteins, and on the other hand it is a major synthetic method encompassing esterification, amidation, Friedel-Crafts reaction and many other processes routinely used both at the laboratory and the industrial...
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In: Journal of Organic Chemistry, 2009, vol. 74, no. 12, p. 4519–4524
A range of N-protected-α-amino acyl-5,7-dinitroindolines 3a−z were prepared in good yields from commercially available N-protected-α-amino acids 1a−z by a two-step sequence of acylation and intramolecular amide N-arylation. Subsequent photochemical acylation of the N-protected-α-amino acyl-5,7-dinitroindolines 3e,g,r afforded the corresponding N-protected-α-amino acid amides 22e,g,r...
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In: Dalton Transaction, 2009, vol. 26, p. 5127-5131
The tungsten-182 Mössbauer spectra of a series of Keggin structure heteropolytungstates, [EW₁₂O₄₀]ⁿ⁻ are reported. There is a very considerable variation in quadrupole coupling at the tungsten nucleus indicating considerable asymmetry in the electron distribution for the more electronegative elements E. The quadrupole coupling correlates well with the structural data, in...
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In: Organic Letters, 2008, vol. 10, no. 15, p. 3175–3178
The intramolecular photocycloaddition of aryl aldehydes containing allene side chains is a versatile reaction as it provides a rapid and efficient access to original complex structures such as 1,3,4-tetrahydro-1,4-epoxy-5-alkylidene-2-benzoxepines 2 and substituted 2-oxa-tricyclo[5.2.2.0]1,5undeca-4,8,10-triene-9-carbaldehydes 3. Novel polycyclic structures are...
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In: Organic Letters, 2007, vol. 9, no. 26, p. 5453 -5456
Photolabile protecting groups have proven their usefulness on many occasions. Their versions as linkers are however less attractive, as robustness and real orthogonality become critical issues. Safety-catch systems, where a preliminary activation phase is necessary, circumvent the problem of premature cleavage. In this work, we introduce a new safety-catch photolabile protecting group, whose...
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In: Organic Letters, 2007, vol. 9, no. 14, p. 2649-2651
The main challenge in developing new wavelength-specific photolabile protecting groups is the rigorous control of the photolysis rate. This rate is controlled by two factors: the chromophore absorbance and the reaction quantum yield. Fine-tuning the properties by changing substituents or structural features is difficult, because both factors are independently affected. By the use of the kinetic...
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In: European Journal of Organic Chemistry, 2007, p. 2073 - 2077
We report here conditions which allow the photoacylation of primary, secondary and tertiary alcohols with N-acetyl-5,7-dinitroindoline under exceptionally mild conditions, at wavelengths harmless to most functional groups, including otherwise photosensitive ones.
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In: Nature, 2007, vol. 446, no. 7135, p. 526-529
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