88702-47-0Relevant academic research and scientific papers
Lewis Base-Catalyzed Enantioselective Conjugate Reduction of β,β-Disubstituted α,β-Unsaturated Ketones with Trichlorosilane: E/ Z-Isomerization, Regioselectivity, and Synthetic Applications
Sugiura, Masaharu,Ashikari, Yasuhiko,Takahashi, Yuka,Yamaguchi, Koki,Kotani, Shunsuke,Nakajima, Makoto
, p. 11458 - 11473 (2019/10/11)
The chiral bisphosphine dioxide-catalyzed asymmetric conjugate reduction of acyclic β,β-disubstituted α,β-unsaturated ketones with trichlorosilane affords saturated ketones having a stereogenic carbon center at the carbonyl β-position with high enantioselectivities. Because the E/Z-isomerizations of enone substrates occur concomitantly, reduction products with the same absolute configurations are obtained from either (E)- or (Z)-enones. Conjugate reduction is accelerated in the presence of an electron-rich aryl group at the β-position of the enone owing to its carbocation-stabilizing ability. Computational studies were also conducted in order to elucidate the origin of the observed enantioselectivity. The regio- and enantioselective reductions of dienones were realized and applied to the syntheses of ar-turmerone, turmeronol A, mutisianthol, and jungianol, which are optically active sesquiterpenes.
One-Pot Synthesis of β,β-Disubstituted α,β-Unsaturated Carbonyl Compounds
Sugiura, Masaharu,Ashikari, Yasuhiko,Nakajima, Makoto
, p. 8830 - 8835 (2015/09/15)
TiCl4-promoted aldol reaction of ketones as aldol acceptors followed by elimination of the titanoxy group from the Ti-aldolates affords β,β-disubstituted α,β-unsaturated carbonyl compounds in a one-pot procedure. The use of additives, such as DMF, N,N,N′,N′-tetramethylethylenediamine, and pyridine, in the elimination step was found to be important.
A NOVEL SYNTHETIC METHOD OF DIHYDRO-4-PYRONE DERIVATIVES AND ITS APPLICATION TO THE SYNTHESES OF ar-ATLANTONE AND (+/-)-ar-TURMERONE
Sakai, Takashi,Miyata, Kazuyoshi,Ishikawa, Mutsumi,Takeda, Akira
, p. 4727 - 4730 (2007/10/02)
Reaction of 1,3-dihalo-3-methyl-2-butanone with t-butyl acetoacetate (NaH) gave t-butyl 3,4-dihydro-2,2,6-trimethyl-4-oxo-2H-pyran-5-carboxylate via the Favorskii-type rearrangement.Michael addition of 4-methylphenyllithium (CuI) followed by ring cleavage
