Mild conditions for Pd-catalyzed carboamination of N-protected hex-4-enylamines and 1-, 3-, and 4-substituted pent-4-enylamines. Scope, limitations, and mechanism of pyrrolidine formation.
Mild conditions for Pd-catalyzed carboamination of N-protected hex-4-enylamines and 1-, 3-, and 4-substituted pent-4-enylamines. Scope, limitations, and mechanism of pyrrolidine formation.
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DOI：
10.1021/jo801631v
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发表时间：
2008-11-21
期刊：
影响因子：
--
通讯作者：
Wolfe JP
中科院分区：
文献类型：
--
作者：
Bertrand MB;Neukom JD;Wolfe JP
弱碱Cs_2CO_3在Pd催化的N-保护的γ-氨基烯烃与芳基溴的碳胺化反应中的使用导致官能团和烯烃取代的耐受性大大增加。衍生自（E）-或（Z）-己-4-烯胺的底物立体特异性地转化为2，1 ′-二取代的吡咯烷产物，其由氮原子和芳基在烯烃上的超面加成产生。4-取代的戊-4-烯胺衍生物的转化以高产率进行，得到2，2-二取代的产物，并且从C1或C3处带有取代基的N-保护的戊-4-烯胺以良好的产率和优异的非对映选择性生成顺式-2，5-或反式-2，3-二取代的吡咯烷。该反应容忍广泛的官能团，包括酯，硝基，和烯醇化酮。这些转换的范围和限制进行了详细描述，沿着与模型，占所观察到的产品立体化学。此外，氘标记实验，这表明这些反应进行通过顺式氨基钯化的中间体钯（芳基）（氨基）配合物，无论程度的烯烃取代或反应条件，也进行了讨论。
The use of the weak base Cs2CO3 in Pd-catalyzed carboamination reactions of N-protected γaminoalkenes with aryl bromides leads to greatly increased tolerance of functional groups and alkene substitution. Substrates derived from (E)- or (Z)-hex-4-enylamines are stereospecifically converted to 2,1′-disubstituted pyrrolidine products that result from suprafacial addition of the nitrogen atom and the aryl group across the alkene. Transformations of 4-substituted pent-4-enylamine derivatives proceed in high yield to afford 2,2-disubstituted products, and cis-2,5- or trans-2,3-disubstituted pyrrolidines are generated in good yield with excellent diastereoselectivity from N-protected pent-4-enylamines bearing substituents at C1 or C3. The reactions tolerate a broad array of functional groups, including esters, nitro groups, and enolizable ketones. The scope and limitations of these transformations are described in detail, along with models that account for the observed product stereochemistry. In addition, deuterium labeling experiments, which indicate these reactions proceed via syn-aminopalladation of intermediate palladium(aryl)(amido)complexes regardless of degree of alkene substitution or reaction conditions, are also discussed.
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影响因子：
15
作者：
CASALNUOVO, AL;CALABRESE, JC;MILSTEIN, D
通讯作者：
MILSTEIN, D
影响因子：
15
作者：
Brice, JL;Harang, JE;Stahl, SS
通讯作者：
Stahl, SS
影响因子：
5.2
作者：
Fritz, Jonathan A.;Nakhla, Josephine S.;Wolfe, John P.
通讯作者：
Wolfe, John P.
影响因子：
5.2
作者：
Bertrand, Myra Beaudoin;Leathen, Matthew L.;Wolfe, John P.
通讯作者：
Wolfe, John P.
影响因子：
2.1
作者：
Bertrand, MB;Wolfe, JP
通讯作者：
Wolfe, JP