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The Buchner ring expansion is a two-step organic C-C bond forming reaction used to access 7-membered rings. The first step involves formation of a carbene from ethyl diazoacetate , which cyclopropanates an aromatic ring.
The Buchner–Curtius–Schlotterbeck reaction is the reaction of aldehydes or ketones with aliphatic diazoalkanes to form homologated ketones. [1] It was first described by Eduard Buchner and Theodor Curtius in 1885 [ 2 ] and later by Fritz Schlotterbeck in 1907. [ 3 ]
Carbenes had first been postulated by Eduard Buchner in 1903 in cyclopropanation studies of ethyl diazoacetate with toluene. [29] In 1912 Hermann Staudinger [30] also converted alkenes to cyclopropanes with diazomethane and CH 2 as an intermediate. Doering in 1954 demonstrated their synthetic utility with dichlorocarbene. [31]
Cyclopropanation is also stereospecific as the addition of carbene and carbenoids to alkenes is a form of a cheletropic reaction, with the addition taking place in a syn manner. For example, dibromocarbene and cis -2-butene yield cis -2,3-dimethyl-1,1-dibromocyclopropane, whereas the trans isomer exclusively yields the trans cyclopropane.
Nursing Children and Young People is a nursing journal covering the practice of pediatric nursing. The journal was established in 1989 as Paediatric Nursing, obtaining its current title in 2014, and is published by RCN Publishing. It is abstracted and indexed in CINAHL, Embase, MEDLINE/PubMed, Scopus, ProQuest, EBSCO databases, and Thomson Gale.
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By Leah Douglas and Julie Steenhuysen (Reuters) -California's public health department reported a possible case of bird flu in a child with mild respiratory symptoms on Tuesday, but said there was ...