18937-82-1Relevant articles and documents
The synthesis of 2-alkylated cyclopentene-1,3-diones: Novel compounds with olfactory properties
Hailes, Helen C.,Isaac, Ben,Javaid, M. Hashim
, p. 29 - 41 (2003)
The syntheses of 2-butyl-4,5-dimethylcyclopent-4-ene-1,3-dione, possessing a buttery jasmine odor, and a series of analogues have been carried out via the synthesis of butenolactones, with subsequent conversion to 4,5-dimethylcyclopent-4-ene-1,3-dione and an alkylation strategy. The compound with the strongest odor characteristics, has also been synthesised using a Pauson-Khand reaction and selective oxidative route.
Mechanistic aspects on the formation of chiral allenes from propargylic ethers and organocopper reagents
Alexakis,Marek,Mangeney,Normant
, p. 8042 - 8047 (1990)
Propargylic ethers react with organocopper reagents to afford allenes by a syn addition to the triple bond followed by a β-elimination of the resulting alkenyl copper species. With use of chiral propargylic ethers and stoichiometric organocopper reagent, it was shown that the β-elimination step is purely anti, resulting in the formation of a chiral allene with 96% optical yield. The same reaction, run with a Grignard reagent RMgX and a catalytic amount of a Cu1 salt, affords allenes through an anti or syn overall process. The crucial step is the β-elimination of the intermediate alkenyl organometallic species, which is of anti type with RMgI and of syn type with RMgCl. Propargylic acetates, which also afford allenes in this reaction, but through a CuIII intermediate, are not sensitive to this "halogen effect".
Palladium-catalyzed chemoselective allylic substitution, suzuki-miyaura cross-coupling, and allene formation of bifunctional 2-B(pin)-substituted allylic acetate derivatives
Kim, Byeong-Seon,Hussain, Mahmud M.,Hussain, Nusrah,Walsh, Patrick J.
supporting information, p. 11726 - 11739 (2014/10/15)
A formidable challenge at the forefront of organic synthesis is the control of chemoselectivity to enable the selective formation of diverse structural motifs from a readily available substrate class. Presented herein is a detailed study of chemoselectivity with palladium-based phosphane catalysts and readily available 2-B(pin)-substituted allylic acetates, benzoates, and carbonates. Depending on the choice of reagents, catalysts, and reaction conditions, 2-B(pin)-substituted allylic acetates and derivatives can be steered into one of three reaction manifolds: allylic substitution, Suzuki-Miyaura cross-coupling, or elimination to form allenes, all with excellent chemoselectivity. Studies on the chemoselectivity of Pd catalysts in their reactivity with boron-bearing allylic acetate derivatives led to the development of diverse and practical reactions with potential utility in synthetic organic chemistry.
Alkylidenesilacyclopropanes derived from allenes: Applications to the selective synthesis of triols and homoallylic alcohols
Buchner, Kay M.,Clark, Timothy B.,Loy, Janice M.N.,Nguyen, Thong X.,Woerpel
supporting information; experimental part, p. 2173 - 2175 (2009/10/24)
Several alkylidenesilacyclopropanes were prepared by silver-mediated silylene transfer to allenes. Oxasilacyclopentanes derived from allenes were prepared with high regio- and diastereoselectivity by a two-step, one-flask silacyclopropanation/carbonyl ins
