20935-29-9Relevant academic research and scientific papers
Unified approach to the sesquiterpenoids, lauranes and cyclolauranes: Total synthesis of (±)-isolaurene
Niyogi,Khatua, Arindam,Bisai, Vishnumaya
, (2019)
A general approach to the total synthesis of sesquiterpene, isolaurene (1a) and cyclolaurene (2a) is featured from commercially available 3-methyl cyclopenten-2-one. The strategy includes a Stork-Danheiser sequence concomitant with a Ni(II)-catalyzed conj
Synthesis of Cyclopentenones with Reverse Pauson-Khand Regiocontrol via Ni-Catalyzed C-C Activation of Cyclopropanone
Jang, Yujin,Lindsay, Vincent N. G.
supporting information, p. 8872 - 8876 (2020/12/02)
A formal [3 + 2] cycloaddition between cyclopropanone and alkynes via Ni-catalyzed C-C bond activation has been developed, where 1-sulfonylcyclopropanols are employed as key precursors of cyclopropanone in the presence of trimethylaluminum. The transformation provides access to 2,3-disubstituted cyclopentenones with complete regiocontrol, favoring reverse Pauson-Khand products, where the large substituent is located at the 3-position of the ring. In the process, the trimethylaluminum additive is thought to play multiple roles, including as a Br?nsted base triggering the equilibration to cyclopropanone and liberation of methane, as well as a source of Lewis acid to activate the carbonyl group toward Ni-catalyzed C-C activation.
Remarkable effect of aluminum reagents on rearrangements of epoxy acylates via stable cation intermediates and its application to the synthesis of (S)-(+)-sporochnol A
Kita,Furukawa,Futamura,Ueda,Sawama,Hamamoto,Fujioka
, p. 8779 - 8786 (2007/10/03)
A remarkable effect of (C6F5O)3Al for promoting the rearrangement of epoxy acylates via stable cation intermediates was found, and new methods for constructing chiral benzylic, vinylic, and acetylenic quaternary carbon centers were developed. During the study, the importance of the ionic nature of the O - metal bond in the intermediates of such epoxides was addressed. This method was applied to the asymmetric total synthesis of (S)-(+)-sporochnol A.
Synthesis of vinyl nonaflates derived from β-ketoesters, 1/4 b-diketones or α-diketones and their palladium-catalyzed cross-coupling reactions with organozinc halides
Bellina, Fabio,Ciucci, Donatella,Rossi, Renzo,Vergamini, Piergiorgio
, p. 2103 - 2112 (2007/10/03)
Cyclic and acyclic β-ketoesters 4, a typical cyclic α-diketone 5 and a typical cyclic β-diketone 6 were converted to the corresponding vinyl nonaflates of general formula 7, 8 and 9, respectively, by reaction with 1.2- 1.5 equiv of NaH in DMF at 20-55 °C followed by treatment with 1.15-1.30 equiv of perfluoro-1-butanesulfonyl fluoride at 20 °C. These vinyl nonaflates, which were purified by MPLC on silica gel, proved to be excellent electrophiles in Pd-catalyzed cross-coupling reactions with aryl-, 1-alkynyl- and alkylzinc chlorides. A variety of cyclic and acyclic tetrasubstituted α,β-unsaturated esters which included stereoisomerically pure compounds, a 2-substituted 3-aryl-2-cyclopentenone and naturally-occurring dihydrojasmone were cleanly synthesized by these smooth and selective cross-coupling reactions.
THE RELATION BETWEEN THE 13C NMR CHEMICAL SHIFTS, THE CONSTANTS OF THE SUBSTITUENTS IN THE ARYL RADICAL, AND THE TOTAL CHARGES OF THE CARBON ATOMS IN 2-METHYL-3-ARYL-2-CYCLOPENTEN-1-ONES
Borisov, E. V.,Skorynin, I. Yu.,Pap, A. A.,Batura, E. V.,Lis, L. G.
, p. 578 - 584 (2007/10/02)
The variation of the 13C chemical shifts and of the charges at the carbon atoms of 2-methyl-3-aryl-2-cyclopenten-1-ones in relation to the nature and position of the substituent in the aryl radical was studied by 13C NMR spectroscopy and quantum chemistry (MNDO) in the Hammett approach.
