Silver-Promoted Benzannulations of Siloxyalkynes with Pyridinium and Isoquinolinium Salts
作者:Jaime R. Cabrera-Pardo、David I. Chai、Sergey A. Kozmin
DOI:10.1002/adsc.201300443
日期:2013.9.16
efficient benzannulations of siloxyalkynes with pyridinium and isoquinolinium salts. Such reactions are successfully promoted by a stoichiometric amount of silver(I) benzolate under mild reaction conditions. This process proceeds via a formal inverse‐electron demand Diels–Alder reaction, followed by fragmentation of the initially produced bicyclic adducts to deliver a range of synthetically useful phenols
Cycloaddition reactions of silyloxyacetylenes with ketenes: synthesis of cyclobutenones, resorcinols, and .DELTA.-6-tetrahydrocannabinol
作者:Conrad J. Kowalski、G. Sankar. Lal
DOI:10.1021/ja00219a073
日期:1988.5
La cycloaddition du cetene avec des composes acetyleniques donne des cyclobutene-2ones. Ces dernieres reagissent avec des composes acetyleniques pour donner des resorcinols et le tetrahydro-6a,7,10,10a cannabinol
La cycloaddition du cetene avec des composes acetyleniques donne des cyclobutene-2ones。Ces dernieres reagissent avec des composes acetyleniques pour donner des resorcinols et le tetrahydro-6a,7,10,10a 大麻
Non-Precious Metals Catalyze Formal [4 + 2] Cycloaddition Reactions of 1,2-Diazines and Siloxyalkynes under Ambient Conditions
作者:Chintan S. Sumaria、Yunus E. Türkmen、Viresh H. Rawal
DOI:10.1021/ol501254h
日期:2014.6.20
Copper(I) and nickel(0) complexes catalyze the formal [4 + 2] cycloaddition reactions of 1,2-diazines and siloxyalkynes, a reaction hitherto best catalyzed by silver salts. These catalysts based on earth abundant metals are not only competent, but the copper catalyst, in particular, promotes cycloadditions of pyrido[2,3-d]pyridazine and pyrido[3,4-d]pyridazine, enabling a new synthesis of quinoline
铜 (I) 和镍 (0) 配合物催化 1,2-二嗪和甲硅烷氧基炔烃的正式 [4 + 2] 环加成反应,该反应迄今为止最好由银盐催化。这些基于富含地球的金属的催化剂不仅有能力,而且铜催化剂,特别是促进吡啶并[2,3- d ]哒嗪和吡啶并[3,4- d ]哒嗪的环加成,使喹啉和异喹啉衍生物,以及环己烯酮与甲硅烷氧基炔烃的正式 [2 + 2] 环加成反应。
Synthesis of Eight-Membered Lactones: Intermolecular [6+2] Cyclization of Amphoteric Molecules with Siloxy Alkynes
作者:Wanxiang Zhao、Zhaobin Wang、Jianwei Sun
DOI:10.1002/anie.201200513
日期:2012.6.18
That's about the size of it: The title molecules react with siloxyalkynes in the presence of a Brønsted acid to deliver medium‐sized lactones through a [6+2] cyclization (see scheme; TIPS=triisopropylsilyl). This process is the first intermolecularsynthesis of such lactones and involves a sequence of several selective ring‐opening/ring‐closing events.
A New Strategy for Efficient Synthesis of Medium and Large Ring Lactones without High Dilution or Slow Addition
作者:Wanxiang Zhao、Zigang Li、Jianwei Sun
DOI:10.1021/ja400883q
日期:2013.3.27
We have developed an efficient method for medium and large ring lactonesynthesis by a conceptually different ring-expansion strategy. The design of an unprecedented ring conjunction mode of oxetene, combined with the appropriate choice of a Lewis acid promoter and an additive, constitutes the key components of the new process. Enabled by this new approach, the reaction does not require high dilution
我们通过概念上不同的扩环策略开发了一种有效的中环和大环内酯合成方法。The design of an unprecedented ring conjunction mode of oxetene, combined with the appropriate choice of a Lewis acid promoter and an additive, constitutes the key components of the new process. 通过这种新方法,反应不需要高度稀释或缓慢添加。