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DMAP-MSN

Lin et al. have developed a new nucleophilic catalytic system for the MBH reaction that consists of dialkylaminopyridine-functionalized mesoporous silica nanospheres (DMAP-MSN). This material is an efficient heterogeneous catalyst for MBH reactions, exhibiting good reactivity, product selectivity and recyclability to give the corresponding adducts in moderate to excellent yields (Scheme 2.235). ... [Pg.196]

The chemical shifts obtained from the solid-state NMR spectra of DMAP-MSN matched well with the solution data of the organic precursors, as shown in Figure 4.8. The results confirmed the presence of the DMAP functionality on the... [Pg.56]

The catalytic performances of the spherical DMAP-MSN catalyst for three different nucleophilic reactions (Baylis-Hillman, acylation, and silylation reactions) were examined (Scheme 4.4). For Baylis-Hillman reaction, only a catalytic amount... [Pg.57]

Chemical Shifts Observed in DMAP-MSN and in the Reference Compounds (DMAP-TES and 4NMe2-Py). [Pg.57]

For acylation and silylation reactions, the steric effect significantly influenced product yield in the DMAP-MSN system. To further investigate the recyclability and stability of DMAP-MSN catalysts, acylation of alcohols was chosen as the model reaction.2 Our results showed that the DMAP-MSN catalysts could be recycled for at least 10 times without losing any catalytic reactivity. The turnover number (TON) of DMAP-MSN catalysts was as high as 3340 for 24 days. [Pg.58]

The 2,2 -bisindole (1384), required for the synthesis of staurosporinone (293) and the protected aglycon 1381, was prepared by a double Madelung cyclization as reported by Bergman. For the synthesis of the diazolactams 1382 and 1383, the glycine esters 1385 and 1386 were transformed to the lactams 1389 and 1390 by DCC/DMAP-promoted coupling with monoethyl malonate, followed by Dieckmann cyclization. The lactams 1389 and 1390 were heated in wet acetonitrile, and then treated with mesyl azide (MsNs) and triethylamine, to afford the diazolactams 1382 and 1383. This one-pot process involves decarboethoxylation and a diazo transfer reaction (Scheme 5.234). [Pg.352]

Scheme 5.12 Baylis-Hillman reaction employing MSN-DMAP. Scheme 5.12 Baylis-Hillman reaction employing MSN-DMAP.
See other pages where DMAP-MSN is mentioned: [Pg.106]    [Pg.55]    [Pg.55]    [Pg.56]    [Pg.57]    [Pg.57]    [Pg.57]    [Pg.58]    [Pg.59]    [Pg.59]    [Pg.59]    [Pg.59]    [Pg.59]    [Pg.60]    [Pg.60]    [Pg.60]    [Pg.60]    [Pg.106]    [Pg.55]    [Pg.55]    [Pg.56]    [Pg.57]    [Pg.57]    [Pg.57]    [Pg.58]    [Pg.59]    [Pg.59]    [Pg.59]    [Pg.59]    [Pg.59]    [Pg.60]    [Pg.60]    [Pg.60]    [Pg.60]    [Pg.106]   
See also in sourсe #XX -- [ Pg.196 ]



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