Furans group

The furan group also serves as a protected carboxylic acid/... 

Neoclerodan-18,19-olides with a furan group on C-12 and Me-17 in a-configuration (50-52). 

The third category is represented with the neoclerodan-18,19-olides, C-9 Spiro linked wih a five member etherocycle bearing a furan group on C-12 ... 

Craft and Gung have disclosed the first transannular (4-1-3) cycloaddition of a symmetrical substrate using an allene function catalyzed by Pd(ll) in reaction with a furan group. The substrate itself is produced by a Grubbs I RCM, and the nonsymmetrical product should be a useful intermediate for the cortistatins (Scheme 33) [70]. 

Polmers bearing pendant furan groups are also photosensitive and some were synthesized, for instance. ... 

In 1969, Craven reported the first example of the DA reaction with the furan/ maleimide system [136]. He synthesized polymers which consisted of chains of the saturated condensation polymer backbone bearing the furan group reacted with maleimides. Since then several patents and papers have been published, all concerning the fabrication of a thermally reversible polymer network bearing DA-reactive furan and maleimide units, either as pendant groups (for reversible cross-linking) [137-147], or as part of the polymer backbone (for reversible polymerization) [148-154]. 

The feasibihty of the Diels-Alder coupling was shown on the example of biodegradable polyester by Ninh and Bettinger [47]. In this case, hyperbranched poly(glycerol-co-sebacate) with pendant furan groups was coupled with a bifunctional maleimide cross-linker to produce an elastomeric material. POSS moieties may serve as cross-linking sites, as well. Ishida et al. [48] have shown how a... 

As follows from Fig. 4.3a, hardness increases from the minimum value 1,71 MPa in absence schungite to 2, 5 MPa, i.e. increases in 1.5 times. The hardness increase, possibly, is caused by formation of hydrogen bridges between furan groups LV and it groups PHB. In more details the mechanism of formation of associates will be stated further. 

In aluminium tris-[n-carbonyl-cyclopentadienyl(dicarbonyl)tungsten] tristetrahydrofuran," the aluminium atom is bonded to three tetrahydro-furan groups and three -OC-W(CO)2Cp groups, and the unit has a mer-configuration. Al-O distances are 1.94 A to THF ligands and 1.827 A to... 

Since the trifluoroacetylation is likewise possible with furan and thiophene under comparable conditions, the relative reactivities have been evaluated. Pyrrole exhibits the highest relative reactivity in the furan group [104]. 

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