Integrating metal-organic frameworks (MOFs) in microelectronics has disruptive potential because of the unique properties of these microporous crystalline materials. Nanoscale patterning is a fundamental step in the implementation of MOFs in miniaturised solid-state devices. Conventional MOF patterning methods suffer from a low resolution and poorly defined pattern edges. Here, we demonstrate for the first time resist-free, direct X-ray and e-beam lithography of MOFs. This process avoids etching damage and contamination, and leaves the porosity and crystallinity of the patterned MOFs intact. The resulting highquality patterns have a record sub-50 nm resolution, far beyond the state of the art in MOF patterning and approaching the mesopore regime. The excellent compatibility of X-ray and e-beam lithography with existing microfabrication processes, both in research and production facilities, provides an avenue to explore the integration of MOFs in microelectronics further. This approach is the first example of direct lithography of any type of microporous crystalline network solid, and marks an important milestone in the processing of such materials.

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Tetraacylgermanes are known as highly efficient photoinitiators. Herein, the synthesis of mixed tetraacylgermanes 4 a–c and 6 a–e with a nonsymmetric substitution pattern is presented. Germenolates are crucial intermediates of these new synthetic protocols. The synthesized compounds show increased solubility compared with symmetrically substituted tetraacylgermanes 1 a–d. Moreover, these mixed derivatives reveal broadened n–π* absorption bands, which enhance their photoactivity. Higher absorption of these new compounds at wavelengths above 450 nm causes efficient photobleaching when using an LED emitting at 470 nm. The quantum yields are in the range of 0.15–0.57, depending on the nature of the aroyl substituents. On the basis of these properties, mixed‐functionalized tetraacylgermanes serve as ideal photoinitiators in various applications, especially in those requiring high penetration depth. The synthesized compounds were characterized by elemental analysis, IR spectroscopy, NMR and CIDNP spectroscopy, UV/Vis spectroscopy, photolysis experiments, and X‐ray crystallography. The CIDNP data suggest that the germyl radicals generated from the new tetraacylgermanes preferentially add to the tail of the monomer butyl acrylate. In the case of 6 a–e only the mesitoyl groups are cleaved off, whereas for 4 a–c both the mesitoyl and the aroyl group are subject to α‐cleavage.

The synthesis of stable triacylgermenolates 3 a,b was achieved by using a multiple silyl abstraction methodology. The formation of these new germenolates was confirmed by NMR spectroscopy and UV‐Vis measurements. Moreover, for the triacylgermenolates 2 and 3 a LIFDI mass spectrometry to characterize these new compounds. Germenolates 3 a,b serve as a starting point for a new triaacylgermane 4 a and two octaacyldigermanes 4 c,d. The formation of these acylgermanes was confirmed by NMR spectroscopy, X‐ray crystallography, UV‐Vis measurements and mass spectrometry. The UV‐Vis absorption spectra of 4 c,d show considerably increased band intensities due to the presence of eight chromophores.

Hier wird ein Syntheseverfahren fürT etraacylgermane Ge[(CO)R] 4 (R = Mesityl (1a), Phenyl (1b)), eine bis dato unbekannte Verbindungsklasse hochwirksamer germaniumbasierter Photoinitiatoren, beschrieben. Tetraacylgermane sind über eine unkomplizierte Eintopfsynthese in Ausbeuten > 85 %z ugänglich. Ihre Strukturen konnten mittels NMR-Spektroskopie,M assenspektrometrie und Einkristallstrukturanalyse bestätigt werden. Das Potenzial von 1a,b als Photoinitiatoren wird durch Photobleaching-(UV-Vis), zeitauflçsende EPR-(CIDEP) und NMR/CIDNP-Untersuchungen sowie Photo-DSC-Studien demonstriert. Bemerkenswerterweise übertreffen Tetraacylgermane die Leistungsfähigkeit von derzeit bekannten Photoinitiatoren fürd ie lichtinduzierte ra-dikalischeP olymerisation im langwelligen Bereich. Prof. N. Moszner Ivoclar Vivadent AG, Schaan (Liechtenstein) Hintergrundinformationen und die Identifikationsnummer (ORCID) eines Autors sind unter: http://dx.