Addition ofthe PÀ H bond in bis(mesitoyl)phosphine, HP(COMes) 2 (BAPH), to a wide variety of activated carbon-carbon double bonds as acceptors was investigated. While this phospha-Michael addition does not proceed in the absence of an additive or catalyst, excellent results were obtained with stoichiometric basic potassium or caesium salts. Simple amine bases can be employed in catalytic amounts, and tetramethylguanidine (TMG) in particular is an outstanding catalyst that allows the preparation of bis(acyl)phosphines, RÀ P(COMes) 2 , under very mild conditions in excellent yields after only a short time. All phosphines RP(COMes) 2 can subsequently be oxidized to the corresponding bis(acyl)phosphane oxides, RPO(COMes) 2 , a substance class belonging to the most potent photoinitiators for radical polymerizations known to date. Thus, a simple and highly atom economic method has been found that allows the preparation of a broad range of photoinitiators adapted to their specific field of application even on a large scale.
A N-hydroxy succinimide (NHS) ester substituted bis(acyl)phosphane oxide (ACTIVE-BAPO) was prepared by phospha-Michael addition and used for an easy one-step BAPO ligation with substrates containing primary amino groups, such as amino acids, proteins, and poly(amidoamine) (PAMAM) dendrimers. Thereby, a range of new molecular and polymeric photoinitators was obtained. Real-time photorheology experiments demonstrated the outstanding effi-ciency of the PAMAM BAPOs as photoinitiators for free radical polymerization. Remarkably, it is found that PAMAM BAPOs also act as crosslinking agents to convert monofunctional methacrylate monomers into thermosetting networks without any further additives. Depending on the number of the attached BAPOs, thermosets with a different degree of crosslinking and swelling capability in water were obtained.
The reactivity of the bis(acyl)phosphide ion [P(COR) 2 ] À (BAP À , R = Ph, Mes) with silicon halides SiX 4 (X = Cl, Br) and pnictogen chlorides ECl 3 (E = As, Sb and Bi) was investigated. The reaction with SiX 4 leads to the hexacoordinate silanes SiX 2 (BAP) 2 in which BAP À is coordinated in the chelating k 2 -O,O' mode, analogously to acac À . Unexpectedly, the coordination behaviour of BAP À differs from the one of acac À in the interpnictogen compounds E(BAP) 3 (E = As, Sb) in which the formation of EÀ P bonds is favoured over k 2 -O,O' chelation via the oxygen centres. Finally, the reaction of BiCl 3 with three equivalents of Na(BAP) leads to the formation of red, crystalline Bi 2 (BAP) 4 , an air stable dibismuthine, as product of a redox reaction.
Phosphane, PH 3 -a highly pyrophoric and toxic gas-is frequently contaminated with H 2 and P 2 H 4 , which makes its handling even more dangerous. The inexpensive metal-organic framework (MOF) magnesium formate, α-[Mg(O 2 CH) 2 ], can adsorb up to 10 wt % of PH 3 . The PH 3 -loaded MOF, PH 3 @α-[Mg(O 2 CH) 2 ], is a non-pyrophoric, recoverable material that even allows brief handling in air, thereby minimizing the hazards associated with the handling and transport of phosphane. α-[Mg(O 2 CH) 2 ] further plays a critical role in purifying PH 3 from H 2 and P 2 H 4 : at 25 °C, H 2 passes through the MOF channels without adsorption, whereas PH 3 adsorbs readily and only slowly desorbs under a flow of inert gas (complete desorption time � 6 h). Diphosphane, P 2 H 4 , is strongly adsorbed and trapped within the MOF for at least 4 months. P 2 H 4 @α-[Mg-(O 2 CH) 2 ] itself is not pyrophoric and is air-and lightstable at room temperature.
Phosphan, PH3 – ein hochpyrophores und toxisches Gas – ist gewöhnlich mit H2 und P2H4 kontaminiert, was seine Handhabung gefährlich macht. Die kostengünstige metallorganische Gerüstverbindung (MOF) aus Magnesiumformiat, α‐[Mg(O2CH)2], kann bis zu 10 wt % PH3 adsorbieren. Das mit PH3 beladene MOF, PH3@α‐[Mg(O2CH)2], ist ein nicht pyrophores, rückgewinnbares Material, das eine kurze Handhabung von PH3 an Luft ermöglicht und die Gefahren bei der Handhabung und dem Transport von Phosphan reduziert. α‐[Mg(O2CH)2] spielt außerdem eine wichtige Rolle bei der PH3‐Reinigung von H2 und P2H4: bei 25 °C diffundiert H2 direkt durch die MOF‐Kanäle ohne Adsorption, PH3 wird adsorbiert und desorbiert nur langsam unter einem Strom von Inertgas (Desorptionszeit≈6 h). Diphosphan, P2H4, wird von dem MOF‐Gerüst stark adsorbiert und bleibt für länger als 4 Monate eingeschlossen. P2H4@α‐[Mg(O2CH)2] selbst ist nicht pyrophor, sondern luft‐ und lichtstabil bei Raumtemperatur.
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