Geometric
<i>E</i>
→
<i>Z</i>
Isomerisation of Alkenyl Silanes by Selective Energy Transfer Catalysis: Stereodivergent Synthesis of Triarylethylenes via a Formal
<i>anti</i>
‐Metallometallation
作者:Svenja I. Faßbender、John J. Molloy、Christian Mück‐Lichtenfeld、Ryan Gilmour
DOI:10.1002/anie.201910169
日期:2019.12.16
An efficient geometrical E→Z isomerisation of alkenyl silanes is disclosed via selective energy transfer using an inexpensive organic sensitiser. Characterised by operational simplicity, short reaction times (2 h), and broad substrate tolerance, the reaction displays high selectivity for trisubstituted systems (Z/E up to 95:5). In contrast to thermal activation, directionality results from deconjugation
The synthesis of silacycles is highly appealing due to their important applications in organic synthesis, medicinal chemistry, and materials chemistry. However, sila-tetralins and sila-benzosuberanes are surprisingly under-represented due to a lack of general methods to access these compounds. We successfully developed a Pd-catalyzed strain-release silicon-based cross-coupling as an unprecedented ring-expansion
New Reagents for the Synthesis of Arylmethyl Ethers and Esters
作者:Gregory Dudley、Philip Albiniak
DOI:10.1055/s-0029-1219531
日期:2010.4
developmentof new arylmethyl transfer (benzylation) reagents for protectingoxygen functional groups under relatively mild and neutral conditions.It begins with an investigation of organosiletanes as surrogatehydroxyl groups, which inspired siletane-functionalized benzyl ethersand forced us to confront the difficulties associated with the synthesisof benzyl ethers. The end result is a new series of neutral oxypyridiniumsalts
Enantioselective synthesis of (+)-anatoxin-a via enyne metathesis
作者:Jehrod B. Brenneman、Rainer Machauer、Stephen F. Martin
DOI:10.1016/j.tet.2004.06.021
日期:2004.8
A concise synthesis of the potent nAChR agonist (+)-anatoxin-a (1) has been completed by a series of nine chemical operations and in 27% overall yield from commercially available d-methyl pyroglutamate (12). The strategy featured the application of a new protocol for the diastereoselective synthesis of cis-2,5-disubstituted pyrrolidines bearing unsaturated sidechains and an intramolecular enyne metathesis
Synthesis of Enantioenriched Allylic Silanes via Nickel-Catalyzed Reductive Cross-Coupling
作者:Julie L. Hofstra、Alan H. Cherney、Ciara M. Ordner、Sarah E. Reisman
DOI:10.1021/jacs.7b11707
日期:2018.1.10
asymmetric Ni-catalyzed reductive cross-coupling has been developed to prepare enantioenriched allylic silanes. This enantioselective reductive alkenylation proceeds under mild conditions and exhibits good functional group tolerance. The chiral allylic silanes prepared here undergo a variety of stereospecific transformations, including intramolecular Hosomi-Sakurai reactions, to set vicinal stereogenic centers
已开发出不对称 Ni 催化的还原交叉偶联来制备对映体富集的烯丙基硅烷。这种对映选择性还原烯基化在温和条件下进行,并表现出良好的官能团耐受性。这里制备的手性烯丙基硅烷经过各种立体定向转化,包括分子内细美-樱井反应,以设置具有优异手性转移的邻位立体中心。