71098-88-9Relevant articles and documents
Synthesis method of 2-benzoxepin compound
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Paragraph 0045; 0055; 0057; 0067; 0069; 0077, (2021/05/29)
The invention discloses a synthesis method of a 2-benzoxepin compound. The method comprises the following specific steps: under the protection of nitrogen, adding N-phenylseleno-phthalimide into a reactor, then adding anhydrous dichloromethane to dissolve the N-phenylseleno-phthalimide, then adding a 1-[(cinnamyl) methyl]-3, 4, 5-trimethoxybenzene compound, taking zinc chloride as a catalyst, reacting at room temperature, adding saturated sodium bicarbonate for quenching after the reaction is finished, extracting by dichloromethane, combining organic phases, drying by anhydrous magnesium sulfate, concentrating under reduced pressure, and performing silica gel rapid chromatographic purification by thin-layer chromatography silica gel to obtain the 2-benzoxepin compound. The method is simple in reaction operation, mild in reaction condition, relatively high in yield, environment-friendly and suitable for large-scale industrialized production.
Biosynthesis of Rotenone and Amorphigenin. Study of the Origins of Isopropenyl-substituted Dihydrofuran E-Rings using Isotopically Labelled Late Precursors
Bhandari, Prabha,Crombie, Leslie,Kilbee, Geoffrey W.,Pegg, Stephen J.,Proudfoot, Geoffrey,et al.
, p. 851 - 864 (2007/10/02)
Whilst epoxidation of rot-2'-enonic acid is the most likely source of dalpanol in Amorpha fruticosa seedlings, administration of (5'R,6'S)-dalpanol shows that it is not an intermediate on the path to rotenone and amorphigenin.Labelled 4'-hydroxy- or 5'-hydroxy-rot-2'-enonic acid also do not qualify as intermediates in rotenone biosynthesis, but they are each converted into amorphigenin with chemospecific attack on the methyl group.By administration and re-isolation of amorphigenin from A. fruticosa seedlings, our earlier conclusion that hydroxylation ofrotenone to form amorphigenin proceeds with even label scrambling between C-7' and C-8', probably via an allylic radical, is confirmed.Competitive double-labelling experiments are employed to support a scheme in which rotenone derives directly from rot-2'-enonic acid by an enzyme-induced radical-type reaction without the intervention of an hydroxylated intermediate, and the two labelled hydroxyrot-2'-enonic acids are similarly cyclised using their methyl groups.The incorporations into amorphigenin of labelled 4- and 5-hydroxyrot-2'-enonic acids, both of which are shown to occur naturally in A. fruticosa, are similar, but only about one sixth that of rotenone.This, and our related biosynthetic work, rests on an extensive programme of isotopic labelling and reconstructive synthesis.Our earlier method for making -rotenone has been improved, and similar procedures adapted for - and -amorphigenin. 8'-Labelled rotenones are made by a positional interchange using addition of benzeneselenenyl chloride and elimination of the selenoxide, whilst -amorphigenin is made via addition of phenylselenophthalimide.Unlabelled amorphigenin can be isotopically labelled by oxidation to the aldehyde and reduction using sodium borodeuteride or borotritide and a method additional to those we have described earlier is given for tritium labelling of rot-2'-enonic acid. - and -Labelling in the 5'-position of 4'- and 5'-hydroxyrot-2'-enonic acids can be attained through the catalytic hydrogenolysis of amorphigenin though special methods must be used to scrub the samples totally free from the latter.Methods based on the hydrolysis of labelled 4'-bromorot-2'-enonic acid are also described, and 4'-tritium-labelled 4'-hydroxyrot-2'-enonic acid is made from unlabelled material, or from rot-2'-enonic acid, by simple oxidation/reduction methods.
STEREOELECTRONIC STABILIZATION IN NON-CHAIR CONFORMATIONS OF SUBSTITUTED-2,3-DIHYDRO-1,4-BENZODIOXEPINS
Lachapelle, Alain,St-Jacques, Maurice
, p. 5033 - 5044 (2007/10/02)
2,3-Dihydro-1,4-benzodioxepin (5) and its 3-substituted derivatives 6-9 have been studied by (13)C and (1)H dynamic NMR in two solvent systems of different polarity.The aromatic signals were found to be quite sensitive to the nature of the seven-membered cyclic geometries and were used as "conformational probes".The results show that the chair (C) conformation is the only form detected at -120 deg C for the parent compound 5 and its 3-methyl derivative 6 whereas the twist-boat (TB) comformation becomes predominant for three derivatives, 3,3-dimethyl 7, 3-metoxy 8 and 3,3-methylmethoxy 9, as a consequence of both steric and stereoelectronic interactions.Furthermore, in the case of 8, the detailed geometry of the TB forms detected reflects on the relative importance of competing stereoelectronic (anomeric and gauche) effects.
