Cyclohexylidene moiety

Fluorinated PAEs with Cardo Cyclohexylidene Moiety... 

S. Ghosh, D. Bera, P. Bandyopadhyay, S. Banerjee, Effect of introduction of cardo cyclohexylidene moiety on gas transport properties of fluorinated poly(arylene ether)s, Eur. Polym. J. 52 (2014) 207-217. 

Figure 4.16 Fluorinated polyamides containing cyclohexylidene moiety [17],...

Bera et al. [59] reported on the gas transport properties of new aromatic poly(ether amide)s containing cyclohexylidene moiety. They investigated the gas transport properties of these membranes for the four different gases (CH, N, O, and CO ). They concluded that the d membranes display good gas selectivity with comparable permeability with previously reported aromatic polyamides. PA 6A showed high CO and permeability and PA 6E showed high permselectivity for COj/CH and OJ gas pairs. 

Bera D, Dasgupta B, Chatterjee S, Maji S, Baneijee S. Gas transport properties of new aromatic polyfether amidejs containing cyclohexylidene moiety. J Membr Sci 2012 407-8. 

The Peterson olefination may also be applied to the preparation of a,P-unsatu-rated esters, thus providing an attractive alternative to the HWE phosphonate method. For example, deprotonation of trimethylsilylacetate with RjNLi followed by addition of cyclohexanone yields the intermediate P-hydroxysilane, which, on elimination of the silicon-oxygen moieties, furnishes ethyl cyclohexylidene-acetate. ... 

Cyclohexylidene and isopropylidene monoketals 47 and diketals 48, 49, and 50 are well-known protected myo-inositol derivatives (Scheme 3-1). Compounds 47 ketalized at the 1,2-cis-positions have been utilized conveniently for the synthesis of various inositol phosphates since 47 can be regioselectively functionalized and prepared in good yield by the conventional ketalization procedure and subsequent partial deprotection of the less stable trans-type ketals from the diketal mixture formed first in the reaction.22 Three diketals S have been also often employed for the synthesis of target inositol derivatives, because they have the following advantages (1) A trans vicinal hydroxyl moiety as well as the 1,2-... 

The cyclohexylidene protecting group has been employed in several syntheses. A preparation of 2,3-0-cyclohexylidene-4-deoxy-L-threose (445) fi om L-( + )-diethyltartrate (lb) in seven steps illustrates one synthetic application (Scheme 99). Conversion of the monobenzyl protected alcohol 443 to its tosylate followed by reduction with sodium borohydride provides the deoxy intermediate 444, which is reductively deprotected and Swem oxidized to 445 in good overall yield. Treatment with benzylamine provides an imine that undergoes a stereoselective carbon-carbon bond forming reaction with a-lithio-A, A -dimethylacetamide in the presence of the Lewis acid zinc bromide to furnish, after Cbz-amine protection, the j9-aminoamide 446. This is converted in four steps to A -acetyl-L-daunosamine (447), a sugar moiety particularly important as the carbohydrate constituent of the anthracycline antibiotics [149]. 

Other anions that can be used in this type of reaction include anions from compounds with a-hydrogen to nitrile group such as phenylacetonitrile, 2-phenylbutyronitrile, and 2-cyclohexylidene-acetonitrile [9]. For example, the reaction of 2-iodoanisole or l-iodo-2-methoxynaphthalene with 2-naphthylacetonitrile anion (24) gave good yields of a,a-diarylated acetonitriles (25) (Eq. 10.10). However, the regioselectivity decreases when the same anion reacts with Ar" with less steric hindrance and substitution at the of the naphthyl 26 moiety begins to be observed (4-MeOCjH and... 

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