Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog Weg 1, Hönggerberg, 8093 Zürich, Switzerland.
School of Chemistry, Lehn Institute of Functional Materials (LIFM), Sun Yat-sen University, 135 West Xingang Road, Guangzhou, 510275, P. R. China.
Chemistry. 2019 Mar 12;25(15):3957-3962. doi: 10.1002/chem.201806116. Epub 2019 Feb 18.
The reaction of Na[OCP] with (R N) ECl (E=P or As; R=alkyl) granted direct access to transient amine-substituted diphospha- and arsaphospha-acrylamide analogues, (R N)E=P(CONR ) 1. Their facile formation allowed for a comprehensive reactivity study. Dimerization yielded the four-membered rings (R N) E P (CONR ) , whereas in the presence of excess Na[OCP], a stepwise [2+2] cycloaddition occured, leading to the sodium salts of carboxotripnictides [(R N)EP CO(CONR )] . These salts served as a reservoir of 1, either by extrusion of Na[OCP] or by reaction with the appropriate (R N) ECl, giving the [4+2]-cycloaddition products (R N)EP(C H )(CONR ) in the presence of 2,3-dimethylbutadiene. The formal conjugate addition product K[(tBuO)(R N)PP(CONR )] was obtained by reaction of Na[(R N)PP CO(CONR )] with tBuOK. In addition, a rare diphosphadigalletane with a ladder-type (R N) Ga P (CONR ) core was isolated from the reaction of Na[OCP] with (R N) GaCl (R=alkyl). The unprecedented pnictogenyl carboxamide compounds were thoroughly characterized, including single-crystal X-ray structure determinations, and mechanisms for their formation were investigated by DFT calculations.
Na[OCP]与(R N) ECl（E=P 或 As；R=烷基）的反应直接得到瞬态胺取代的二膦酰胺和胂酰胺类似物（R N)E=P(CONR ) 1。它们的易形成性允许进行全面的反应性研究。二聚化生成四元环（R N) E P (CONR )，而在过量 Na[OCP]存在下，逐步发生[2+2]环加成反应，生成羧三价氮化物的钠盐[(R N)EP CO(CONR )]。这些盐是 1 的储存库，可通过挤出 Na[OCP]或与适当的（R N) ECl 反应来实现，在 2,3-二甲基丁二烯存在下生成[4+2]-环加成产物（R N)EP(C H )(CONR )。通过 Na[(R N)PP CO(CONR )]与 tBuOK 的反应，得到了形式上的共轭加成产物 K[(tBuO)(R N)PP(CONR )]。此外，从 Na[OCP]与(R N) GaCl（R=烷基）的反应中分离出了具有罕见的 ladder-type（R N) Ga P (CONR )核的二膦杂环戊二烯。对前所未有的磷杂酰胺化合物进行了彻底的表征，包括单晶 X 射线结构测定，并通过 DFT 计算研究了它们的形成机制。
