24850-33-7Relevant articles and documents
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Seyferth, D.,Weiner, M. A.
, p. 4797 - 4800 (1961)
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Ueno,Okawara
, p. 1893 (1979)
Photoredox-Catalyzed C-F Bond Allylation of Perfluoroalkylarenes at the Benzylic Position
Sugihara, Naoki,Suzuki, Kensuke,Nishimoto, Yoshihiro,Yasuda, Makoto
supporting information, p. 9308 - 9313 (2021/06/28)
Site-selective and direct C-F bond transformation of perfluoroalkylarenes was achieved with allylic stannanes via an iridium photoredox catalyst system. The present defluoroallylation proceeds exclusively at the benzylic position through perfluoroalkyl radicals generated by a single-electron transfer from an excited photoredox catalyst to perfluoroalkylarenes. A variety of perfluoroalkyl groups are applicable: linear perfluoroalkyl-substituted arenes such as Ar-nC4F9and Ar-nC6F13and heptafluoroisopropylarenes (Ar-CF(CF3)2) underwent site-selective defluoroallylation. DFT calculation studies revealed that thein situgenerated Bu3SnF traps F-to prevent a retroreaction from the unstable perfluoroalkyl radical intermediate, and the radical intermediate favorably reacts with allylic stannanes. The synthesis of a bis(trifluoromethyl)methylene unit containing compound, which is an analog that is useful as a pharmaceutical agent for the prophylaxis or treatment of diabetes and inflammatory diseases, demonstrated the utility of this reaction.
Forging C-C Bonds with Hindered Nucleophiles and Carbonyl Electrophiles: Reactivity and Selectivity of Allylic Tin Reagents/n-BuLi
Cormier, Morgan,Ahmad, Maha,Maddaluno, Jacques,De Paolis, Micha?l
, p. 4920 - 4927 (2018/02/07)
Under activation with n-BuLi, trialkylstannanes containing crotyl-, geranyl-, and phenyldienylmethyl appendages were reacted with efficiency and selectivity to various ketone and enone electrophiles with low reactivity. The straightforward process gives access to tertiary alcohols that are vicinal to quaternary carbons. With α,α′-dimethoxy-γ-pyrone, on the other hand, the grafting of a dienyl side chain was effected to prepare dienyl α′-methoxy-γ-pyrone in a stereo- and regioselective and convergent manner. Furthermore, the advantages of this route were highlighted for the preparation of organolithium species at low temperature with the formation of a minimum amount of salts. Synthetic manipulations were demonstrated to illustrate the potential of the chemistry for constructing acyclic and cyclic terpene scaffolds.
Practical Stannylation of Allyl Acetates Catalyzed by Nickel with Bu3SnOMe
Komeyama, Kimihiro,Itai, Yuuhei,Takaki, Ken
supporting information, p. 9130 - 9134 (2016/07/14)
A practical and scalable nickel-catalyzed allylic stannylation of allyl acetates with Bu3SnOMe is described. A variety of acyclic and cyclic allyl acetates, even with base-sensitive moieties, undergoes the stannylation by using NiBr2/4,4′-di-tert-butylbipyridine (dtbpy)/Mn catalyst system to afford highly functionalized allyl stannanes with excellent regioselectivity and yields. Furthermore, the scope of protocol is also extended by the reaction of propargyl acetates, giving rise to propargyl or allenyl stannanes. Additionally, a unique diastereoselectivity using the nickel catalyst different from the palladium was demonstrated for the stannylation of cyclic allyl acetates. In the reaction, inexpensive and stable nickel complexes, abundant reductant (Mn), and atom-economical stannyl source were used.
