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Christina M. Longo Yang Wei Mary F. Roberts Prof. Scott J. Miller Prof. 《Angewandte Chemie (International ed. in English)》2009,48(23):4158-4161
The big “DIP”per : The preparation of both l,l ‐DIP and l,d ‐DIP (see structures) involves a complex case of double asymmetric induction in the key step of the synthesis. The differential ability of each isomer to contribute to thermoprotection in the context of a key enzyme has been assessed and both isomers of DIP are shown to possess biological activity.
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Gérard Cahiez Dr. Laura Foulgoc Alban Moyeux 《Angewandte Chemie (International ed. in English)》2009,48(16):2969-2972
Aryl–alkyl cross‐coupling products are obtained by the iron‐catalyzed oxidative heterocoupling of organozinc reagents under mild conditions. This novel reaction pathway is versatile, allowing for the use of primary and secondary aliphatic diorganozinc reagents as coupling partners as well as tolerating functionalized aryl‐ and alkylzinc reagents.
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Jing Tan Xianxiu Xu Dr. Lingjuan Zhang Yifei Li Qun Liu Prof. 《Angewandte Chemie (International ed. in English)》2009,48(16):2868-2872
Up to four adjacent stereocenters can be formed stereoselectively in the construction of a pyrrolizidine unit through a novel organocatalytic reaction that involves treatment of various dienones with ethyl isocyanoacetate (see scheme; DBU=1,8‐diazabicyclo[5.4.0]undec‐7‐ene). Mechanisms for this atom‐economic, one‐pot synthesis have been proposed.
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Mamoru Tobisu Dr. Naoto Chatani Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(20):3565-3568
Seeing the sites : The Suzuki–Miyaura reaction of substrates containing multiple coupling sites has been performed in a directed manner through the reactivity modulation of the boron moiety (see scheme). Several other strategies are also discussed.
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Barbara Wucher Michael Moser Dr. Stephanie A. Schumacher Frank Rominger Dr. Doris Kunz Priv.‐Doz. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(24):4417-4421
Metal‐to‐metal allyl transfer : Using the first structurally characterized rhodium η1‐allyl complexes it is shown that the σ‐bound allyl substituent can be transferred from the RhIII complex to a RhI complex in a fast equilibrium. This process may account for the decrease in regioselectivity observed in allylic alkylation reactions in which complex 1 is used as a catalyst.
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Vivek Polshettiwar Dr. Rajender S. Varma Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(7):1582-1586
Magnetic attraction not filtration : A magnetic nanoparticle‐supported ruthenium hydroxide catalyst (see figure) was readily prepared from inexpensive starting materials and shown to catalyze the hydration of nitriles with excellent yield in a benign aqueous medium. Catalyst recovery using an external magnetic field, superior activity, and the inherent stability of the catalyst system are additional sustainable attributes of this protocol.