A novel method for generation of carbenoid from α-chloro sulfoxides: A new and versatile procedure for one-carbon homologation of carbonyl compounds to carbonyl compounds having an α-alkyl substituent
Addition of the carbanion of 1-chloroalkyl p-tolyl sulfoxides to carbonylcompound gave the adducts, which were treated with a base followed by t-butyllithium to afford one-carbon homologated carbonylcompounds having an alkyl group at the α-position, via the β-oxido carbenoids, in moderate to good yields.
Short and Versatile Two-Carbon Ring Expansion Reactions by Thermo-Isomerization: Novel Straightforward Synthesis of (±)-Muscone, Nor- and Homomuscones, and Further Macrocyclic Ketones
作者:Matthias Nagel、Hans-Jürgen Hansen、Georg Fráter
DOI:10.1055/s-2002-19759
日期:——
the ring-expanded ketone as corresponding α-, and β-substituents, respectively. This novel thermal 1,3-C shift reaction therefore provides a new access to short syntheses of many alkyl-substituted macrocyclic ketone derivatives [e.g. (′)-muscone and analogues] in a systematic manner.
在 600 °C 至约 650 °C 的温度下,1-乙烯基取代的中环和大环环烷醇衍生物在流动反应器系统中的热异构化直接导致扩环大环酮。乙烯基部分的烷基取代基分别作为相应的α-和β-取代基局部特异性地转移到扩环的酮上。因此,这种新颖的热 1,3-C 变换反应为许多烷基取代的大环酮衍生物 [例如 (')-麝香酮和类似物] 以系统方式进行短程合成提供了新途径。
The synthesis of 14-membered macrocyclic ethers
作者:Dean S. Clyne、Larry Weiler
DOI:10.1016/s0040-4020(99)00846-7
日期:1999.11
involved either the Baeyer-Villiger ring expansion of a cyclic ketone or the macrolactonization of a hydroxy acid to give a lactone. The lactone carbonyl was removed either by conversion to an intermediate thionolactone obtained by reaction with Lawesson's reagent and reduction or by direct reduction using a boron trifluoride etherate mediated sodium borohydride reaction.
Neue Macrolide und einige Sesquiterpen-Derivate aus demGalbanum-Harz
作者:Roman Kaiser、Dietmar Lamparsky
DOI:10.1002/hlca.19780610736
日期:1978.11.1
New Macrolides and Some Sesquiterpenoid Derivatives Occurring in Galbanum Absolute
新的大环内酯类化合物和一些加倍青素中的倍半萜衍生物
Diradical-Promoted (<i>n </i>+ 2 − 1) Ring Expansion: An Efficient Reaction for the Synthesis of Macrocyclic Ketones
作者:Georg Rüedi、Matthias A. Oberli、Matthias Nagel、Hans-Jürgen Hansen
DOI:10.1021/ol048701e
日期:2004.9.1
[reaction: see text] A diradical-promoted (n + 2 - 1) ringexpansionreaction based on vinyl side chain insertion (+2C) and decarbonylation (-1C) has been developed. Flash vacuum pyrolysis (FVP) of medium- and large-ring 2-trimethylsilyloxy-2-vinyl-cycloalkanones at 500-600 degrees C affords the one-carbon ring-expanded cycloalkanones in good yields. Methyl groups on the vinyl moiety are transformed