93434-80-1Relevant articles and documents
Mukaiyama reagent-promoted metal-free preparation of alkynyl sulfones and phosphonates under mild conditions
Qi, Danyang,Dong, Wanrong,Peng, Zhihong,Zhang, Yingjun,An
, (2019/08/01)
An efficient and mild route for the formation sulfur or phosphor-substituted alkynes was herein demonstrated. The Mukaiyama reagent-mediated transformation started from easily-accessible substrates without carbon-carbon triple bonds, and the reaction proceeded under mild conditions (room temperature) in a one-pot manner, requiring for no transition metal-catalysts. The practical protocol featured for good functional groups tolerance (up to 41 examples) and high efficiency (up to 91% yields) towards alkynyl sulfones and alkynyl phosphonates at low cost.
ALKYATION STUDIES OF 5-EXO-METHYLENE SUBSTITUTED ISOXAZOLIDINES
Padwa, Albert,Carter, Stephen P.,Chiacchio, Ugo,Kline, Donald N.,Perumattam, John
, p. 2639 - 2646 (2007/10/02)
1,3-Dipolar cycloaddition of nitrones to phenylsulphonylallene gives in high yield and with complete regiospecificity 5-methyleneisoxazolidines.These on treatment with base and subsequent reaction with electrophiles afford both α- and γ-substituted products.With methyl iodide as the electrophile, only the α-methylated product was isolated.In contrast, reaction of the 5-exo-methylene-4-phenylsulphonylisoxazolidine with allyl bromide afforded the γ-allyated product.Formation of this was shown to be via direct γ-attack, rather than by α-attack, followed by a 3,3-sigmatropic rearrangement.Further studies show that the product ratio is controlled by a sensitive interplay between thermodynamic and steric factors and is very dependent on the nature of the electrophile used.