Formation of 9,10-Unsaturation in the Mitomycins: Facile Fragmentation of β-Alkyl-β-aryl-α-oxo-γ-butyrolactones
摘要:
[GRAPHICS]A facile fragmentation of beta -alkyl-beta -aryl-alpha -oxo-gamma -butyrolactones is reported. A study to assist in the elucidation of the mechanism of the reaction is also revealed.
Formation of 9,10-Unsaturation in the Mitomycins: Facile Fragmentation of β-Alkyl-β-aryl-α-oxo-γ-butyrolactones
摘要:
[GRAPHICS]A facile fragmentation of beta -alkyl-beta -aryl-alpha -oxo-gamma -butyrolactones is reported. A study to assist in the elucidation of the mechanism of the reaction is also revealed.
Baeyer–Villigeroxidation of cyclobutanones is achieved in current developed protocol with 10-methylacridinium perchlorate (AcrH+ClO4−) as a novel organocatalyst both with irradiation at room temperature and without irradiation at elevated temperature. Excellent yields of the corresponding lactones are obtained and the possible mechanism has been proposed.
Palladium-catalyzed, asymmetric Baeyer–Villiger oxidation of prochiral cyclobutanones with PHOX ligands
作者:Kimberly S. Petersen、Brian M. Stoltz
DOI:10.1016/j.tet.2011.04.046
日期:2011.6
method for the conversion of prochiral 3-substituted cyclobutanones to enantioenriched γ-lactones through a palladium-catalyzed Baeyer–Villigeroxidation using phosphinooxazoline ligands in up to 99% yield and 81% ee. Lactones of enantiopurity ≥93% could be obtained through a single recrystallization step. Importantly, 3,3-disubtituted cyclobutanones produced enantioenriched lactones containing a β-quaternary
Baeyer–Villiger monooxygenase-catalyzed desymmetrizations of cyclobutanones. Application to the synthesis of valuable spirolactones
作者:María Rodríguez-Mata、Iván Lavandera、Vicente Gotor-Fernández、Vicente Gotor、Susana García-Cerrada、Javier Mendiola、Óscar de Frutos、Iván Collado
DOI:10.1016/j.tet.2015.12.071
日期:2016.11
A series of γ-butyrolactone derivatives, including some spiranic ones, was obtained through desymmetrization of the corresponding prochiral 3-substituted cyclobutanones via Baeyer–Villiger monooxygenase (BVMO)-catalyzed oxidation. After reaction optimization using several commercial enzymes, both antipodes of various lactones were synthesized in most cases with >90% conversion and >80% enantiomeric
Efficient and selective: Two lipophilic catalysts were used for Baeyer–Villiger (BV) oxidations to give lactones in high yields (see scheme). Cascadereactions involving this BV oxidation were used to selectively obtain either unsaturated carboxylic acids or hydroxylactones in high yields from β‐silyl cyclohexanones.
The present invention relates to a method for manufacturing an ester from a ketone or an aldehyde, which is a reactive substrate, by a Baeyer-Villiger oxidation reaction using hydrogen peroxide, and in this method, as a catalyst, M(BAr
4
)
n
, which is a metal borate, is used (M represents an alkali metal or an alkaline earth metal; Ar represents an aryl; and n is the same number as the valence of M). For example, when cyclohexanone was used as the reactive substrate, and Sr[B(3,5-CF
3
C
6
H
3
)
4
]
2
was used as the catalyst, ε-caprolactone was obtained at an isolated yield of 82%.