35085-33-7Relevant academic research and scientific papers
Catalytic Dibenzocyclooctene Synthesis via Cobalt(III)–Carbene Radical and ortho-Quinodimethane Intermediates
te Grotenhuis, Colet,van den Heuvel, Naudin,van der Vlugt, Jarl Ivar,de Bruin, Bas
supporting information, p. 140 - 145 (2017/12/13)
The metalloradical activation of ortho-benzallylaryl N-tosyl hydrazones with [Co(TPP)] (TPP=tetraphenylporphyrin) as the catalyst enabled the controlled exploitation of the single-electron reactivity of the redox non-innocent carbene intermediate. This method offers a novel route to prepare eight-membered rings, using base metal catalysis to construct a series of unique dibenzocyclooctenes through selective Ccarbene?Caryl cyclization. The desired eight-membered-ring products were obtained in good to excellent yields. A large variety of aromatic substituents are tolerated. The proposed reaction mechanism involves intramolecular hydrogen atom transfer (HAT) to CoIII–carbene radical intermediates followed by dissociation of an ortho-quinodimethane that undergoes 8π cyclization. The mechanism is supported by DFT calculations, and the presence of radical-type intermediates was confirmed by trapping experiments.
Oxidative coupling reactions of 1,3-diarylpropene derivatives to dibenzo[a,c]cycloheptenes by PIFA
Hackeloeer, Kristina,Schnakenburg, Gregor,Waldvogel, Siegfried R.
supporting information; experimental part, p. 6314 - 6319 (2011/12/01)
The oxidative cyclization reactions of a variety of α- benzylcinnamates can be selectively performed with hypervalent iodine as an oxidant. The dibenzo[a,c]cycloheptenes were isolated in up to 55 % yield. When an oxo substrate is applied, the yield was significantly increased. With this synthetic approach, a central intermediate for the synthesis of metasequirin-B was obtained in three steps from very simple starting materials. For this transformation, both aryl moieties have to be activated.
Pharmaceutical amides, and preparation, formulations and use of thereof
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, (2008/06/13)
Compounds of the general formula STR1 wherein Ph is a phenyl group which is optionally substituted by one or more substituents selected from halo (i.e. fluoro, chloro, bromo or iodo), C1-4 alkyl, amino, C1-4 alkylamino, di-C1-4 alkylamino, nitro, sulphonyl, aminosulphonyl, trihalomethyl, carboxy, C1-4 alkoxycarbonyl, amido, C1-4 alkylamido C1-4 alkoxy, C2-4 alkenyl, cyano, aminomethyl or methylsulphonyl; Ra and Rb, which may be the same or different, each represents a hydrogen or alkali metal (e.g. sodium or lithium) atom or a C1-4 (e.g. ethyl) group; m is 0 or 1; Y is a group of formula: or a group of formula: STR2 where R1 is hydrogen or methyl; R2 is alkyl of 1 to 3 carbon atoms or is methylthiomethyl; and Z is --OR3 or --NR4 R5 where R3, R4 and R5 are each hydrogen or alkyl of 1 to 4 carbon atoms (i.e. methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, or t-butyl) and R3 can further be phenylalkyl having 1 to 3 carbon atoms in the alkylene moiety thereof, or phenyl; and basic salts thereof. These compounds have an advantageous enkephalinase inhibitory activity which renders the compounds useful in medical therapy, e.g. to prolong and/or potentiate in a mammal, the effects of endogenous or exogenous enkephalins. The latter includes synthetic enkepalin analogues.
