68884-85-5Relevant academic research and scientific papers
NEW PHOTOINITIATORS
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Page/Page column 46, (2010/02/14)
The invention relates to novel photoinitators of formulae (I), (II), (III), (IV), (V) and (VI) wherein R1 and R2 are each independently of the other C1-C8alkyl; C1-C4alkyl substituted by OH, C1-C4alkoxy, -COO(C1-C8alkyl), (C1-C4alkyl)-COO-, -CN, benzyl, phenyl or by -N(R15)(R16); C3-C6alkerlyl, benzyl, -CH2-C6H4-(C1-C4alkyl) or phenyl; or R1 and R2 together are unbrarched or branched C2-C9alkylene or C3-C6-oxa- or -aza-alkylene; R3, R4, R5 and R6 are each independently of the others hydrogen, C1-C8alkyl, C3-C6alkenyl, benzyl, -CH2-C6H4-(C1-C4alkyl) or phenyl; R3 and R4 together and/or R5 and R6 together are unbranched or branched C2-C9alkylene; A is CI, Br, -O-R9, -N(R11)(R12) or -S-R18, A' is -O-, -NH- or -NR11-; A" is CI, Br, -O-R9, -N(R11)(R12) or -S-R18 or hydrogen, X is -O-R10 or -N(R13)(R14), n is an integer from 1 to 10, preferably an integer from 1 to 4, especially 1, 2 or 3; R7 is a linker; R8 is a bivalent C2-C3alkylele radical.
Acylation of aromatic substrates with ketenes. An example of vinyl oxocation reactivity.
Fountain, K.R.,Heinze, Pamela,Sherwood, Mark,Maddex, Dave,Gerhardt, Greg
, p. 1198 - 1205 (2007/10/02)
Acylations of aromatic substrates with ketenes involve the reactivity of species similar to vinyl cations.Resonance stabilization of ketene-aluminum chloride complexes seems to make these complexes less reactive than corresponding vinyl cations.The kinetic isotope effect of the reaction with dimethylketene and benzene is 1.06, compatible with vinylcation cases, but not with acylation with CH3COBF4 types of electrophiles.Substrate specificity was determined from k (toluene)/k (benzene) values.It was 47.2 for dimethylketene and 173.7 for diphenylketene.The diphenylketene-aluminum chloride complex could be isolated.
