92736-73-7Relevant academic research and scientific papers
A nickel(ii)-catalyzed asymmetric intramolecular Alder-ene reaction of 1,7-dienes
Liu, Wen,Zhou, Pengfei,Lang, Jiawen,Dong, Shunxi,Liu, Xiaohua,Feng, Xiaoming
supporting information, p. 4479 - 4482 (2019/04/26)
A highly diastereo- and enantioselective intramolecular Alder-ene reaction with an alkene as the enophile has been developed by using a chiral N,N′-dioxide/nickel(ii) complex as the catalyst. This protocol provides a facile route towards the synthesis of diverse 3,4-disubstituted chroman, tetrahydroquinoline, piperidine and thiochroman derivatives in high yields with good to excellent diastereo- and enantioselectivities.
Synthesis of Allyl- and Prenylcoumarins via Microwave-Promoted Tandem Claisen Rearrangement/Wittig Olefination
Schmidt, Bernd,Riemer, Martin
supporting information, p. 141 - 149 (2015/12/26)
Allyl, dimethylallyl, crotyl, and prenyl ethers of various aromatic ortho-hydroxy carbonyl compounds undergo a tandem sequence of Claisen rearrangement, carbonyl olefination, and cyclization upon microwave irradiation in the presence of a stabilized ylide. The products are multiply substituted 6- or 8-allylated or prenylated coumarins (2H-chromen-2-ones).
Enantioselective alkynylation reactions to aldehydes: The effects of aromatic substituents upon the enantioselectivity
Tyrrell, Elizabeth,Tesfa, Kibur Hunie,Millet, Julien,Muller, Christophe
, p. 3099 - 3105 (2008/02/10)
Asymmetric alkynylation reactions to linear alkyl and substituted aromatic aldehydes have been accomplished in good yields and with a range of selectivities. For aromatic aldehydes we observed that the selectivity of the alkynylation reaction appears to d
A diastereoselective cobalt-mediated synthesis of benzopyrans using a novel variation of an intramolecular Nicholas reaction in the key cyclisation step: Optimisation and biological evaluation
Mann, Alastair,Muller, Christophe,Tyrrell, Elizabeth
, p. 1427 - 1438 (2007/10/03)
A range of novel intramolecular cyclisation reactions between an organocobalt stabilised cation and a trisubstituted alkene have been accomplished that provide a concise route for the diastereoselective synthesis of a range of functionalised benzopyrans. In addition to the usual Lewis acids employed in the Nicholas reaction our studies have identified several other reagents for effecting the cyclisation reaction. In some examples sub-stoichiometric quantities of Lewis acid were successfully employed. These studies were concluded with a biological evaluation of specific derivatives, conducted by comparing their activity with the antihypertensive agent cromakalim 2, a drug whose mode of action is known to occur via the modulation of potassium channel activity.
Biosynthetic Studies on Tajixanthone and Shamixanthone, Polyketide Hemiterpenoid Metabolites of Aspergillus variecolor
Ahmed, Salman A.,Bardshiri, Esfandiar,McIntyre, C. Rupert,Simpson, Thomas J.
, p. 249 - 274 (2007/10/02)
The biosynthesis of tajixanthone and related metabolites of Aspergillus variecolor has been studied by incorporation experiments with simple and advanced precursors labelled with the stable isotopes 13C, 2H and 18O.Tajixanthone is shown to be derived through ring cleavage of an octaketide-derived anthraquinone with introduction of two dimethylallyl moieties.From the results of isotopic labelling experiments and chemical studies on model compounds, an overall biosynthetic pathway is proposed and information on the mechanisms of interconversion of proposed intermediates is obtained.
Domino Reactions. One-Pot Preparation of Fluorenoisoquinoline Derivatives from Conjugated Ketene Imines
Molina, Pedro,Alajarin, Mateo,Vidal, Angel,Fenau-Dupont, J.,Declerq, J. P.
, p. 4008 - 4016 (2007/10/02)
Iminophosphoranes 4, derived from ethyl α-azido-2-(allyloxy)-3-methoxycinnamates, react with ketenes to give the corresponding ketene imines, which by thermal treatment at 150-160 deg C undergo a consecutive electrocyclic ring closure/Claisen rearrangement/second ring closure/double aromatization process to give isoquinoline derivatives 7 and/or the previously unknown fluorenoisoquinolines 9 in moderate yields.Similarly, iminophosphoranes 14 derived from ethyl α-azido-2,3-disubstituted-4-(allyloxy)cinnamates reacted with diphenyl ketene to give the intermediate ketene imines, which at 150-160 deg C undergo a cascade of pericyclic reactions to give the isoquinolines 15 and the pentacyclic compounds 16 in moderate yields.
