2- Benzyl-6,6-dimethoxy

Purine, 1,6-dihydro-8,9-dimethyl-6-thioxo-synthesis, 5, 583 Purine, 2,6-dimethoxy-synthesis, 5, 596 Purine, 2,6-dimethoxy-7-methyl-rearrangement, 5, 558 Purine, 2,7-dimethyl-halogenation, 5, 547 Purine, 7,9-dimethyl-UV spectra, 5, 517 Purine, 8,8-dimethyl-synthesis, 5, 580 Purine, 6-dimethylamino-mass spectra, 5, 519 occurrence, 5, 600 Purine, 6-dimethylamino-9-benzyl-alkylation, 5, 531 Purine, 3,7-dimethyl-6,8-dioxo-methylation, 5, 534 Purine, 6,8-dioxo-alkylation, 5, 534... 

The authors repeated the experiment with two, more strongly retained, solutes m-dimethoxy benzene and benzyl acetate. These solutes were found to elute at (k ) values of 10.5 and 27.0 respectively on a silica column operated with the same mobile phase. The results obtained are shown as similar curves in Figure 13. The m dimethoxy benzene, which eluted at a (k ) of 10.5, also failed to displace any ethyl acetate from the silica gel even when more than 0.5 g of solute resided on the silica surface. Consequently, the m-dimethoxy benzene must have also interacted with the surface by a sorption process. 

This was confirmed by an independent analytical method by Spath and Boschan, and by a synthesis of pellotine by Spath and Becke, starting from the benzyl ether of 2-hydroxy-3 4-dimethoxyacetophenone, which was converted by aminoacetal into the Schiff s base (V). This, on treatment with sulphuric acid (73 per cent.), followed by warm water, gave 8-hydroxy-6 7-dimethoxy-l-methyh 5oquinoline (VI), of which the methiodide, m.p. 188-189-5°, on reduction furnishes pellotine (IV). From dZ-pellotine so formed Spath and Kesztler, by a special process of fractionation, isolated 1-pellotine having — 15-2° (CHCI3), for which... 

Knabe et al. (271-274) later observed that 6,7-dimethoxy-2-methyl-1,2-dihydroisoquinolines (175), possessing either a free or a substituted benzyl group in position 1, readily rearrange to 3,4-dihydroisoquinoline salts (176) on treatment with dilute acids. 

Raney Nickel W2 or W4, EtOH, 85-100% yield. Mono- and dimethoxy-substituted benzyl ethers and benzaldehyde acetals are not cleaved under these conditions, and trisubstituted alkenes are not reduced. 

Discovery and development of A-benzyl-4-(5,6-dimethoxy-l-oxo-indan-2-ylmethyOpiperidine hydrochloride (donepezil hydrochloride) for treatment of Alzheimer s disease 98YGK320, 99YZ101. 

Hydrogenolysis of aromatic carbonyls occurs mainly by conversion to the benzyl alcohol and its subsequent loss. If hydrogenolysis is desired, the usual catalyst is palladium 38). Hydrogenolysis is facilitated by polar solvent and by acid (55). For instance, hydrogenation of 3,3-dicarbethoxy-5,8-dimethoxy-l-tetralone (5) over 5% Pd-on-C gave 6 quantitatively 54) when hydrogen absorption ceased spontaneously. 

Isoquinoline, 2-acetyl-l, 2,3,4-tettahydro-6,7-dimethoxy-l-inethylene-, 4 Isoquinoline, 2-benzoyl-l -benzy 1-1-cyano-1,2-dihydro- [1-Isoquinolinecarbo-mtrile, 2-benzoyl-l, 2-dihydro-l -(phenjlmethyl)-), 23 Isoquinoline, 2-benzoyl-l -cyano-1,2-di-hydro l-Isoquinohnecarbomtrile, 2-ben2oyl-l, 2-dihydro-], 20 ISOQUINOLINE, 1-BENZYL- [ISOQUINOLINE, HPHENYLMFTHYL)-], 19 Isoquinoline, 3,4-dihydro-6,7-dimethoxy-l-methyl-, 4... 

Benzopyran-3-one, l,4-dihydro-6,7-dimethoxy-], 55, 45 Isocyamde, benzyl-, 55, 98 Isocyanide, butyl-, 55, 98 ISOCYANIDE, tert-butyl- [Isocyamde, 1,1-dimethylethyl-], 55, 96 Isocyamde, cyclohexyl-, 55, 98 Isocyamde, dodecanyl-, 55, 98 Isocyamde, ethyl, 55,98 Isocyamde, methyl, 55, 98 Isocyamde, phenyl-, 55, 98 (-)-2,3 4,6-Di-0-isopropylidene-2-keto-L-gulomc acid, hydrate [L-jcy/o-2-Hex-ulosomc acid, bis-<9-( 1 -mcthylcthyl-ldene)-], 55,80, 81 ISOXAZOl F, 3-(4-chlorophenv1)-5-(4-methoxyphenyl)-, 55, 39 Isoxazole,5 -(4-chloropheny l)-3-(4-me th-oxyphenyl)-, 55,42... 

Brommethyl-benzyl)- bzw. 5,6-Dimethoxy-2-(3,4-dimethoxy-2-brommethyl-bcnzyl)-isochinolinium-bromid wird in DMF unter Dehydrohalogenierung zu 5,6,11,12-Tetrahydro-5-aza-l,2-benzanthracen bzw. Xylopinin cyclisiert1 ... 

Benzyl groups having 4-methoxy (PMB) or 3,5-dimethoxy (DMB) substituents can be removed oxidatively by dichlorodicyanoquinone (DDQ).181 These reactions presumably proceed through a benzylic cation and the methoxy substituent is necessary to facilitate the oxidation. 

It is interesting to note that among initiators studied, a benzyl ketal type initiator (2,2-dimethoxy-2-phenyl acetophenone) is more active than other initiators of acetophenone type. 2,2-Dimethoxy-2-phenyl acetophenone is more active than BME, probably due to the presence of the extra methoxy group on the -carbon, which gives a more active phenyldimethoxy methyl radical (and it further cleaves to give an even more active methyl radical) than the phenylmethoxy methyl radical from BME (4). It is known that the phenylmethoxy methyl radical dimerizes easily and thus loses some of its role as a radical in a... 

Prepare 3,5-dimethoxy benzyl alcohol by reducing the acid with lithium aluminum hydride as described elsewhere here, by hydrogenating the aldehyde (2-3 atmospheres H2, room temperature,Pt02 in ethanol - or by the NaBH4 method), in five steps as described in J ACS 70,666(1948), or prepare (II) directly by the doborane procedure. 

Fig. 3 Multisweep cyclic voltammogram (6 scans) trace-crossing effect during potentiodynamic polymerization of N-benzyl-3,4-dimethoxy-pyrrole in acetonitrile, 0.1 M TBAPFe, +1% H2O, = 200 mV s T = 298 K.

---