General Methodology for the Preparation of 2,5-Disubstituted-1,3-oxazoles
作者:David R. Williams、Liangfeng Fu
DOI:10.1021/ol902833p
日期:2010.2.19
Deprotonation of 2-(phenylsulfonyl)-1,3-oxazole (1) readily provides a useful C-5 carbanion that is reactive with a variety of electrophiles. Aldehydes and ketones are useful substrates, and the formation of 5-iodo- and 5-tri-n-butylstannyl oxazoles affords access to cross-coupling reactions. Subsequent nucleophilic displacement of the 2-phenylsulfonyl group provides a general route for the synthesis of 2,5-disubstituted-1
Total Synthesis of Ajudazol A by a Modular Oxazole Diversification Strategy
作者:Philipp Wollnitzke、Sebastian Essig、Jan Philipp Gölz、Karin von Schwarzenberg、Dirk Menche
DOI:10.1021/acs.orglett.0c02188
日期:2020.8.21
The totalsynthesis of the potent respiratory chain inhibitor ajudazol A was accomplished by a concise strategy in 17 steps (longest linear sequence). The modularapproach was based on a direct oxazole functionalization strategy involving a halogen dance reaction for selective halogenation in combination with a challenging combination of sp2–sp2 and sp2–sp3 Negishi cross coupling reactions. The applicability
Total Synthesis of (+)-Ileabethoxazole via an Iron-Mediated Pauson–Khand [2 + 2 + 1] Carbocyclization
作者:David R. Williams、Akshay A. Shah
DOI:10.1021/ja5043462
日期:2014.6.18
describe the total synthesis of (+)-ileabethoxazole (1) using a Stille cross-coupling reaction of propargylic stannanes with 5-iodo-1,3-oxazoles to produce 1,1-disubstituted allenes (11). An iron-mediated [2 + 2 + 1] carbocyclization yields a novel cyclopentenone for elaboration to 1. Site-selective palladium insertion reactions allow for regiocontrolled substitutions of the heterocycle. Asymmetric copper
Methodology for the Synthesis of Substituted 1,3-Oxazoles
作者:David Williams、Liangfeng Fu
DOI:10.1055/s-0029-1219374
日期:2010.3
The halogen dance isomerization is a facile and preparatively effective pathway for the synthesis of 2,4,5-trisubstituted 1,3-oxazoles.
Studies on Selective Metalation and Cross-Coupling Reactions of Oxazoles
作者:Dirk Menche、Raphael Wagner、Philipp Wollnitzke、Sebastian Essig、Jan P. Gölz
DOI:10.1055/a-2126-0720
日期:2023.12
that was based on the different pK a values of these positions, while a halide at C4 may be introduced by an optimized halogen dance reaction. Efficient protocols for subsequent sp2–sp2 and sp2–sp3 cross-coupling reactions of the derived oxazolyl halides were then established. This modular approach was applied in the total synthesis of ajudazol A and a selected analogue, demonstrating the general feasibility