Functionalized carbonyl compounds

Oxidative carbonylations have acquired a growing importance during the last few years, owing to the development of new and selective catalytic systems, mainly based on palladium, which are able to promote ordered sequences of transformations under mild conditions with formation of highly functionalized carbonyl compounds in one step starting from very simple building blocks. 

The step common to both of these reactions is electrophilic attack of a hypervalent iodine species at the a-carbon of the carbonyl compounds to yield an intermediate 3. Nucleophilic attack of methoxide ion or tosy-loxy ion with the concomitant loss of iodobenzene results in a-functionalized carbonyl compounds (Scheme 2). 

From reactions of ammonia, amines or formamide with functionalized carbonyl compounds... 

Asymmetric Hydrogenation of Functionalized Carbonyl Compounds. (R)-(5)-BPPFOH is designed to have a secondary interaction with a carbonyl substrate through the hydroxy group on the side chain of the ferrocene ring. This additional interaction... 

The most common NCN synthons used are amidines, guanidines, ureas and thioureas. The two-carbon units arc usually suitably functionalized carbonyl compounds. 

The Bredereck modification which uses an a-halo- (or otherwise functionalized) carbonyl compound with formamide has not received the attention that might have been expected. The synthesis of the imidazolepropanol 3 from 3-bromo-2-methoxytetrahydropyran provides one of the only examples (Eq. 2). 

The reactions of amidines or guanidines with a-functionalized carbonyl compounds continue to be utilized for the synthesis of imidazoles. Thus, the mixed anhydride of acetic and chloroacetic acids reacts with symmetrical diarylguanidines to give l-aryl-2-arylaminoimidazolin-4-ones, and there is competitive formation of imidazoles and pyrimidines in the reaction of benzamidine with 3-bromobenzo-4-pyrones (18). Imidazoles are minor products, but are favored in nonpolar solvents. The use of a-dicarbonyl compounds with guanidine gives 2-amino-4-hydroxy-4-methyl-4//-imid-azoles, which give excellent yields of 2-aminoimidazoles on catalytic hydrogenation. " ... 

SOME PRODUCTS OF ORGANOTITANIUM TRIISOPROPOXIDES [RTi(OiPr)3] WITH FUNCTIONALIZED CARBONYL COMPOUNDS. THE BONDS MADE DURING THE REACTION ARE DRAWN BOLD. 

Because of the Lewis acid properties of DIBAH, the reduction of functionalized carbonyl compounds often shows an interesting stereoselectivity (Section 3.2.4). 

The homogeneous hydrogenation of functionalized carbonyl compounds gives remarkable results with catalysts of the type RUX2L (X = halide, L = atropisomeric ligands). These bis(trialkyl phosphine) ligands have a C2 axis. BINAP is their main representative. ... 

Functionalized carbonyl compounds may be reduced by chiral reagents or, if the functional group is chiral, by achiral reagents. 

Aldol reactions. Highly functionalized carbonyl compounds are produced using diketene" and 2,2-dialkoxycyclopropanecarboxylic esters in these condensations. An intramolecular reaction provides access to 2-alkoxycarbonyl-2-cycloalke-... 

Cyclic ureas 1092 and 1094 can be prepared in satisfactory yields (54 and 77%, respectively) by condensation of N,N -dialkylureas of type 1090 with glyoxal 1091 or of urea 1088 with a-functionalized carbonyl compounds 1093, followed by hydro-genolysis or removal of water [787-789]. 

Homologation of aldehydes can be achieved by reaction of the anion (26) with the aldehyde, metallating with BuLi, and hydrolysing the intermediate thus obtained. " The alkenyl-lithiums (27) and (28) provide routes to functionalized carbonyl compounds, both cyclic and acyclic, on reaction with a variety of conventional electrophiles. By employing bulky substituents at the carbonyl group of the enones (29a and b), a -activity is enforced. Lithium amides may be carbonylated to give the corresponding carbamoyl-lithiums (30), which are useful acyl anion equivalents. ... 

The methodology known as direct a-heterofunctionalization of carbonyl compounds was comprehensively reviewed in 2006 [1] and therefore only the most recent developments [2] in this research area since then are considered in this section. These will be presented by the reaction that led to the formation of the new carbon-heteroatom bond, excluding of those in which the hybridization of the previously functionalized carbonyl compound is modified. 

Biological/Medical Applications in water,creatinine in body fluids,telmisartan quantifying aldehyde-functionalized (carbonyl compound) DNA analyzing microperoxidases (microperoxidase substrate) analyzing/detecting peroxidases (peroxidase substrate) ... 

---