Cycloalkanone alkanone

Figure 6. Bitter taste of some ketones (yj 2-alkanones cycloalkanones (n) total number of C-atoms...

Another method involves the l-bromo-2-alkanol derivative, 11/44, which was prepared from cycloalkanone 11/42 as indicated in Scheme II/7. Compound 11/44 forms a magnesium salt which decomposes to give the 2-phenylcyclo-alkanone 11/46, enlarged by one carbon atom [35] [41]. The yields are good ... 

TABLE 13. Electroreductive cyclization of 2-[2- and 3-cyano-alkyl] alkanones and cycloalkanones ... 

Ring expansion of cycloalkanones. 1-Trimethylsilyloxybicyclo[n.l.0]alkanes (1), prepared by Simmons-Smith reaction with silyl enol ethers of cycloalkanones, react with ferric chloride in DMF containing pyridine to form a 3-chlorocycIo-alkanone (2) in fair to high yield. Dehydrochlorination (sodium acetate) yields a 2-cycloalkenone (3) containing one more carbon atom than the starting cycloalkanone. 

Asymmetric Induction on the Nucleophile The use of the tBu-PHOX ligand led to the first catalytic enantioselective Tsuji allylations of simple alkanone enol derivatives 62. These mild, operationally straightforward and stereoselective reactions described by Stoltz et al. [52] produce chiral cycloalkanones 63 with quaternary stereocenters at the a-position with high enantiopurities and in excellent chemical yields (Scheme 12.31). Mechanistic studies showed the incorporation of an O-bound enolate in the intermediate Pd-allyl complex [53]. Further investigations on the substrate scope led to several applications in the synthesis of natural products [54]. Recently, a similar approach was used to afford enantiopure quaternary lactams 65 that intercept synthetic intermediates previously used in the synthesis of the Aspidospcrma alkaloids quebrachamine and rhazinilam, but that were previously only available by chiral-auxiliary-assisted approaches or as racemic mixtures (Scheme 12.32) [55],... 

Ketones are called alkanones, the ending -e of the alkane replaced with -one. An exception is the smallest ketone, propanone, for which lUPAC has accepted the common name acetone. The carbonyl carbon is assigned the lowest possible number in the chain, regardless of the presence of other substituents or the OH, C=C, or C C functional groups. Aromatic ketones are named as aryl-substituted alkanones. Ketones, unlike aldehydes, may also be part of a ring, an arrangement that gives compounds called cycloalkanones. Polyketones are labeled -dione, -trione, and so on. 

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