- Critical Ligand and Salt Effects in Organomagnesiate-Promoted 3,3-Disubstituted Phthalides Synthesis from 2-Iodobenzoate Derivatives
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Phthalides, also called isobenzofuranones, are widespread in many biologically active compounds and natural products. To date, most of their synthetic routes are non-convergent. Herein we report a convergent route using a metal halogen exchange (MHE) strategy. Indeed MHE of easily available 2-iodobenzoate derivatives, using the bimetallic organomagnesiate complex (rac)-(BIPHEN)BuMgLi, where (rac)-BIPHEN is (rac)-5,5′,6,6′-tetramethyl-3,3′-di-t-butyl-1,1′-biphenyl-2,2′-diol, followed by addition of a ketone which lead to an intramolecular cyclisation, and the formation of a series of diverse 3,3-disubstituted isobenzofuranones in good yield. Among the several MHE agents investigated, (rac)-(BIPHEN)BuMgLi was the only one to make such a process possible with full tolerance of various reactive functional substituents useful for subsequent transformations. The synthetic pathway to access the magnesiate has been found to play a prominent role in its reactivity. Therefore, the bimetallic magnesiate complex has been characterized by solution-state 1H, 7Li and 1H DOSY NMR experiments.
- Touchet, Sabrina,Yeardley, Callum,O'Hara, Charles T.,Gros, Philippe C.
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p. 4835 - 4845
(2021/09/22)
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- Saturated oxygen and nitrogen heterocycles: Via oxidative coupling of alkyltrifluoroborates with alkenols, alkenoic acids and protected alkenylamines
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Saturated heterocycles are important components of many bioactive compounds. The method disclosed herein enables a general route to a range of 5-, 6- and 7-membered oxygen and nitrogen heterocycles by coupling potassium alkyltrifluoroborates with heteroat
- Shikora, Jonathan M.,Um, Chanchamnan,Khoder, Zainab M.,Chemler, Sherry R.
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p. 9265 - 9269
(2019/10/22)
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- Scalable Electrochemical Dehydrogenative Lactonization of C(sp2/sp3)-H Bonds
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A practical, electrochemical method is developed for the direct dehydrogenative lactonization of C(sp2/sp3)-H bonds under external oxidant- and metal-free conditions, delivering diverse lactones, including coumarin derivatives with excellent regioselectivity. The scalable nature of this newly developed electrochemical process was demonstrated on a 40 g scale following an operationally simple protocol. The remote lactonization of C(sp3)-H bonds would constitute an important synthetic advance toward electrochemical C-O bond formation.
- Zhang, Sheng,Li, Lijun,Wang, Huiqiao,Li, Qian,Liu, Wenmin,Xu, Kun,Zeng, Chengchu
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supporting information
p. 252 - 255
(2018/01/17)
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