Kaupp G, Schmeyers J, Boy J
Org. Chem. I, Universität Oldenburg, Germany.
Chemosphere. 2001 Apr;43(1):55-61. doi: 10.1016/s0045-6535(00)00324-6.
Unexpected organic solid-state reactions in the gas-solid and stoichiometric solid-solid versions are highly promising new tools for solvent-free sustainable synthesis and production if they occur with 100% yield. Costly workup is obsolete, no wastes are formed and resources and energy saved. More than 500 published 100%-yield, solid-state reactions in 25 reaction types cover virtually all fields of synthetic organic chemistry. Atomic force microscopy (AFM) reveals that solid-state reactions require long-range molecular movements and are strictly and sensibly guided by the crystal packing. Three steps govern the issue: phase rebuilding, phase transformation, and crystal disintegration (detachment). If one of these fails, or if liquid phases are not avoided, the reaction will usually not run to completion. Repeated creation of fresh contacts of crystallites is essential in solid-solid reactions. New, otherwise inaccessible and highly reactive products are most easily obtained. Cooling below eutectic temperatures, but also thermal activation above room temperature, may be necessary. Liquids may be solidified by cooling or inclusion complexation. Typical single-step, multi-step and cascade reactions have been performed with 100% yield using commonly available starting materials in various fields. Upscaling to the kilogram scale has been achieved under various conditions. Further upscaling to technical size productions seems possible.
气固和化学计量固固形式的意外有机固态反应是用于无溶剂可持续合成与生产的极具前景的新工具，前提是它们能以100%的产率发生。昂贵的后处理过时了，不会形成废物，还能节省资源和能源。已发表的25种反应类型中超过500个100%产率的固态反应几乎涵盖了合成有机化学的所有领域。原子力显微镜（AFM）显示，固态反应需要长程分子运动，并且严格且合理地受晶体堆积的引导。有三个步骤决定了这个问题：相重建、相变和晶体解体（分离）。如果其中任何一个步骤失败，或者如果没有避免液相，反应通常不会进行到底。在固固反应中，微晶反复形成新的接触至关重要。最容易获得新的、否则难以获得且高活性的产物。可能需要冷却至共晶温度以下，也可能需要在室温以上进行热活化。液体可通过冷却或包合络合固化。在各个领域中，使用常见的起始原料以100%的产率进行了典型的单步、多步和级联反应。在各种条件下已实现了扩大到千克规模。进一步扩大到工业规模生产似乎是可行的。
