- benzyl pair (2, 4, 6-trimethyl benzoyl) phosphine oxide of the preparation method
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The invention discloses a preparation method of phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide as an efficient free radical photoinitiator. The preparation method of phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide comprises the concrete steps of with 2,4,6-trimethylbenzaldehyde as a raw material, enabling 2,4,6-trimethylbenzaldehyde and phenylphosphine oxide to be subjected to condensation reaction in the existence of a catalyst, and then, carrying out oxidation reaction. Extraction and solvent replacement are not needed and continuous reaction can be realized in the reaction process. The preparation method of phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide, disclosed by the invention, is low in price, environment-friendly, easy to operate and suitable for realizing industrialization.
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- Remarkably robust monomeric alkylperoxyzinc compounds from tris(oxazolinyl)boratozinc alkyls and O2
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Metal alkylperoxides are remarkable, highly effective, yet often thermally unstable, oxidants that may react through a number of possible pathways including O-O homolytic cleavage, M-O homolytic cleavage, nucleophilic O-atom transfer, and electrophilic O-atom transfer. Here we describe a series of zinc alkyl compounds of the type ToMZnR (ToM = tris(4,4-dimethyl-2-oxazolinyl)phenylborate; R = Et, n-C3H 7, i-C3H7, t-Bu) that react with O2 at 25 °C to form isolable monomeric alkylperoxides ToMZnOOR in quantitative yield. The series of zinc alkylperoxides is crystallographically characterized, and the structures show systematic variations in the Zn-O-O angle and O-O distances. The observed rate law for the reaction of ToMZnEt (2) and O2 is consistent with a radical chain mechanism, where the rate-limiting SH2 step involves the interaction of ?OOR and ToMZnR. In contrast, ToMZnH and ToMZnMe are unchanged even to 120 °C under 100 psi of O 2 and in the presence of active radical chains (e.g., ?OOEt). This class of zinc alkylperoxides is unusually thermally robust, in that the compounds are unchanged after heating at 120 °C in solution for several days. Yet, these compounds are reactive as oxidants with phosphines. Additionally, an unusual alkylperoxy group transfer to organosilanes affords ToMZnH and ROOSiR3'.
- Mukherjee, Debabrata,Ellern, Arkady,Sadow, Aaron D.
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scheme or table
p. 13018 - 13026
(2012/10/08)
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