Enantioselective synthesis of anti- and syn-homopropargyl alcohols via chiral Brønsted acid catalyzed asymmetric allenylboration reactions.
Enantioselective synthesis of anti- and syn-homopropargyl alcohols via chiral Brønsted acid catalyzed asymmetric allenylboration reactions.
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DOI：
10.1021/ja3031467
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发表时间：
2012-07-04
影响因子：
15
通讯作者：
Roush, William R.
中科院分区：
文献类型：
--
作者：
Chen, Ming;Roush, William R.
描述了手性布朗斯台德酸催化的不对称联烯基硼化反应。在优化条件下，手性磷酸（S）-4催化（M）-1与醛的烯丙基硼化反应，以高收率和良好的对映选择性合成了反式高炔丙醇2.在对映异构体磷酸（R）-4存在下，（M）-1与芳香醛的错配烯基硼化反应也可以得到具有良好非对映选择性和优异对映选择性的顺式异构体3。引入到2和3中的甲基的立体化学由丙二烯基硼酸酯（M）-1的手性控制，而新的羟基立构中心的构型由在这些反应中使用的手性磷酸催化剂的对映选择性控制。这种方法的合成效用进一步证明了在三重不对称合成的各种反，反立体三元组，其直接合成构成了一个重大的挑战，使用前几代的羟醛和巴豆基金属试剂。
Chiral Brønsted acid catalyzed asymmetric allenylboration reactions are described. Under optimized conditions, anti-homopropargyl alcohols 2 are obtained in high yields with excellent diastereo- and enantioselectivities from stereochemically matched aldehyde allenylboration reactions with (M)-1 catalyzed by the chiral phosphoric acid (S)-4. The syn-isomers 3 can also be obtained in good diastereoselectivities and excellent enantioselectivities from the mismatched allenylboration reactions of aromatic aldehydes using (M)-1 in the presence of the enantiomeric phosphoric acid (R)-4. The stereochemistry of the methyl group introduced into 2 and 3 is controlled by the chirality of the allenylboronate (M)-1, whereas the configuration of the new hydroxyl stereocenter is controlled by the enantioselectivity of the chiral phosphoric acid catalyst used in these reactions. The synthetic utility of this methodology was further demonstrated in triple asymmetric syntheses of a variety of anti,anti-stereotriads, the direct synthesis of which has constituted a significant challenge using previous generations of aldol and crotylmetal reagents.
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影响因子：
16.6
作者：
Canales, Eda;Gonzalez, Ana Z.;Soderquist, John A.
通讯作者：
Soderquist, John A.
影响因子：
15
作者：
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通讯作者：
Kalesse, Markus
影响因子：
5.2
作者：
Chen M;Roush WR
通讯作者：
Roush WR
影响因子：
5.2
作者：
Chen M;Roush WR
通讯作者：
Roush WR
影响因子：
3.6
作者：
Denmark, SE;Fujimori, S;Pham, SM
通讯作者：
Pham, SM