Appel et al., “A Wittig Reaction with 2-Furyl Substituents at the Phosphorus Atom: Improved (Z) Selectivity and Isolation of a Stable Oxaphosphetane Intermediate,” Eur. J. Org. Chem., 2002(7)1143-1148, 2002.
Wittig reaction is a type of synthesis reaction which involves the formation of the alkene from the reaction of a carbonyl compound such as ketone or aldehydes with Wittig reagent {eq}\left( {{\rm{R}} = {\rm{PP}}{{\rm{h}}_{\rm{3}}} \right) {/eq}.Answer...
The E enol lactone (IV) is available from (I) and (II) by Wittig reaction, the intermediate (III) being identified by its crystal structure (P1, Z=2).doi:10.1002/chin.198911106ABELL, A. D.CLARK, B. M.ROBINSON, W. T.WILEY‐VCH Verlag GmbHCheminform...
The one-pot palladium-catalyzed allylic alkylation and Wittig reaction of phosphorus ylides with various aldehydes and ketenes has been realized, which produce skipped dienes, including trisubstituted alkenes and tetrasubstituted allenes, respectively (see scheme), in moderate to good overall yields.关键...
Studies on the Wittig Reaction. XV. A Direct Preparation of ω-Unsaturated Bromides via Solid/Liquid Transferred Wittig Reactions of ω-Bromoalkyltriphenyl Phosphonium Salts with Aldehydesalkylation, arylation, dealkylation, dearylation, C-acylation, olefination...
In the thermal pathway, the imine bonds can undergo a reversible intermolecular exchange reaction with a nucleophile6,7,8,9, leading to a temporary ring-opening of the bicyclic compound (Fig. 1a, brown). In this open form, the side arms can slip through or undergo an intramolecular imine ...
(N-isocyanimine)triphenylphosphorane, tertiary amines, and carboxylic acids resulted in the formation of 1,3,4-oxadiazoles in moderate to good yields through a consecutive oxidative Ugi/aza-Wittig reaction, enabling the direct functionalization of sp3C-H bonds adjacent to the nitrogen atom. This ...
Among the numerous synthetic methods to prepare C-glycosyl derivatives, we have developed and used for several years the Wittig reaction on sugar γ-lactones, which gives an efficient access to functionalized C-glycosylidene compounds (commonly called exo-glycals), and their subsequent stereoselective ...
然而,关于催化不对称aza-Wittig反应的研究较为少见,其在有机合成中的应用价值也未被充分挖掘。近日,清华大学药学院唐叶峰课题组在《美国化学会志》(Journal of the American Chemical Society)上发表题为“Chiral Bisphosphine-Catalyzed Asymm...
The signal of an extremely air sensitive and thermally unstable intermediate, four-membered ring oxaphosphetane in the Wittig reaction was detected for the first time at subambient temperature using liquid secondary ion mass spectrometry (LSIMS) and atmospheric pressure ionization (API) mass spectrometr...