97367-33-4Relevant academic research and scientific papers
Rhodium-Catalyzed Intermolecular Carbonylative [2 + 2 + 1] Cycloaddition of Alkynes Using Alcohol as the Carbon Monoxide Source for the Formation of Cyclopentenones
Kim, Ju Hyun,Song, Taemoon,Chung, Young Keun
supporting information, p. 1248 - 1251 (2017/03/14)
A highly regioselective rhodium-catalyzed intermolecular carbonylative [2 + 2 + 1] cycloaddition of alkynes using alcohol as a CO surrogate to access 4-methylene-2-cyclopenten-1-ones has been developed. In this transformation, the alcohol performs multiple roles, including generating the Rh-H intermediate, functioning as the CO source, and assisting in the isomerization of the alkyne. Alkynes can act as both the olefin and the alkyne partner in the cyclopentenone core.
Nazarov approach to 4-benzoyloxymethyl-cyclopent-2-enone, a precursor to the helminthosporols
Belardi, Justin K.,Curtis, Lindsay A.,Clareen, Steven S.,Shimp, Heidi L.,Leimkuhler, Catherine E.,Simonowicz, Nicole L.,Casillas, Eduard
, p. 1633 - 1640 (2007/10/03)
A short, scalable route to 4-hydroxymethylcyclopent-2-enone, based upon a silicon-directed Nazarov cyclization, is described. Noteworthy in this study is the success of the cyclization with an oxygenated substrate. Copyright Taylor & Francis, Inc.
Investigation of the Cyclopentenone Formation via the α-Alkynone Cyclisation: Synthesis of the Acorone Intermediate 8-Methylspirodeca-3,7-dien-2-one
Ackroyd, John,Karpf, Martin,Dreiding, Andre S.
, p. 338 - 344 (2007/10/02)
As a further application of the cyclopentenone formation A-->C via the thermal α-alkynone cyclisation B-->C and in order to test the fate of an isolated C,C-double bond within a molecule under these conditions, we investigated the synthesis of the acorone intermediate 3 starting from the known carboxylic acid 1.The α-alkynone 2 was obtained from 1 via the acyl chloride 6 and a Pd(II)-catalysed route (22percent).The thermolysis of 2 at 550 deg provided the target molecule 3 (48percent) together with the product 9 (20percent) of a competing intramolecular ene reaction and its dimer 10 (4percent).At a higher thermolysis temperature (650 deg), the spiro ketone 3 was found to be unstable, affording the retro-Diels-Alder fragments 4-methylidene-2-cyclopentenone (12) (33percent) and isoprene (32percent).A further example of the influence of an isolated double bond on the yield of the cyclopentenone-formation sequence A-->C was provided by the comparison of the annelation 14-->20 (5percent overall with Pd(II)-catalysed acylation) with that of its non-olefinic analogue 17-->21 (53percent overall with Friedel-Crafts acylation).
