南方科技大学刘柳团队报道了一种结晶的锡炔。相关研究成果发表在2024年6月17日出版的《自然—化学》。

合成含有较重的14族元素（R¹–C≡E–R²，E=Si、Ge、Sn、Pb）的杂核炔烃类似物是一个长期的挑战。由路易斯碱稳定的中性甲硅烷基（R¹–C≡Si（L）–R²）和锗炔（R¹–C≡ Ge（L）-R²）在低温下获得了足够的结构表征稳定性。

该文中，研究人员展示了在室温下通过战略性地使用体积庞大的环状膦配体，与体积庞大的三苯基取代基来分离无碱锡炔（R¹–C≡Sn–R²）。尽管该化合物具有π-电子强离域的等位基因结构，但它表现出相邻的两亲碳和锡中心，形成了具有离子性质的碳-锡多键。

锡烯表现出类似于卡宾或锡烯的反应性，与1-金刚烷基异氰酸酯和2，3-二甲基-1，3-丁二烯反应。此外，其碳锡键可以被Et₃N·HCl饱和或被异丙基异氰酸酯裂解。

附：英文原文

Title: A crystalline stannyne

Author: Wang, Xin-Feng, Hu, Chaopeng, Li, Jiancheng, Wei, Rui, Zhang, Xin, Liu, Liu Leo

Issue&Volume: 2024-06-17

Abstract: The synthesis of heteronuclear alkyne analogues incorporating heavier group 14 elements (R1–C≡E–R2, E=Si, Ge, Sn, Pb) has posed a long-standing challenge. Neutral silynes (R1–C≡Si(L)–R2) and germynes (R1–C≡Ge(L)–R2) stabilized by a Lewis base have achieved sufficient stability for structural characterization at low temperatures. Here we show the isolation of a base-free stannyne (R1–C≡Sn–R2) at room temperature, achieved through the strategic use of a bulky cyclic phosphino ligand in combination with a bulky terphenyl substituent. Despite an allenic structure with strong delocalization of π-electrons, this compound exhibits adjacent ambiphilic carbon and tin centres, forming a carbon–tin multiple bond with ionic character. The stannyne demonstrates reactivity similar to carbenes or stannylenes, reacting with 1-adamantyl isocyanide and 2,3-dimethyl-1,3-butadiene. Additionally, its carbon–tin bond can be saturated by Et3N·HCl or cleaved by isopropyl isocyanate.

DOI: 10.1038/s41557-024-01555-4

Source: https://www.nature.com/articles/s41557-024-01555-4