Cyclic group

Section 19 15 An intramolecular esterification can occur when a molecule contains both a hydroxyl and a carboxyl group Cyclic esters are called lactones and are most stable when the nng is five or six membered... 

Intramolecular addition of amines to carbonyl groups (cyclic imines)... 

Anhydrides contain two carbonyl groups joined by a single oxygen atom. Symmetrical anhydrides have two identical alkyl groups bonded to the carbonyl carbons, and mixed anhydrides have two different alkyl groups. Cyclic anhydrides are also known. 

Activated carbon, in keeping with the enhanced complexity of carbon-based chemistry, possesses an extensive array of surface moieties, including hydroxyl groups, carboxylic acid groups, aldehyde groups, keto groups, cyclic ethers, and lactone groups. 

Ethers are characterized by the —O— functional group, where the oxygen atom links either alkyl or aromatic groups. Cyclic ethers, with various ring sizes, are called epoxides. O... 

PROTECTING GROUPS - Cyclic imide disulfides from primary amines can be prepared by the scheme below. Treatment with mercaptoethanol under very mild conditions gives back the starting amine. 

The identified compounds were classified into four groups cyclic imides, pyridines, chain fragments and cyclopentanones, as presented in Fig. 9 [65]. Of these compounds, the cyclic imides, pyridines and chain fragments gen-... 

Metallocenes 21-23 were found to bind mono- and dicarboxylic acids in organic solvents through complementary hydrogen bonds with their amide (N—H... O) and pyridine (O-H...N) groups. Cyclic voltammetry studies in CH2CI2 revealed cathodic shifts in the Fc /Fc redox couples, with the redox response to complexation of the monoacid decanoic acid by 21 and 22 ( — 25 mV and... 

In 2001, Du Bois and co-workers developed the intramolecular amination of diverse C—H bonds, including aliphatic ones, by employing the commercially available Rh-catalyst [Rh2(OAc)4] and oxidant PhI(OAc)2. Inspired by this work, Muller and co-workers realized intra- and intermolecular amidation reactions by in situ formed nitrene species. Employing the chiral dirhodium Rh2(S-NTTL)4 developed by their group, cyclic sulfamidates 104 were synthesized in good yields and stereocontrol with sulfamates 103 and PhI(OAc)2 as the nitrene precursors (Scheme 1.37). Subsequently, they... 

Fignre 4.33 shows the spectrum of cyclohexane, a cyclic alkane that has no methyl gronps, only methylene groups. Cyclic alkanes show similar absorption peaks to the straight-chain (acyclic) alkanes. Note the differences in this spectrum compared with that of hexane. The C-H stretching band appears narrower (no broadening due to overlap of CH3 stretches with the methylene stretches), the two peaks clearly match the methylene peaks listed in the table (lower wavennmber than the corresponding methyl peaks), there is no peak at 1375 cm , which confirms the absence... 

Cyclic trimmer n. Strictly, a polymer, in cyclic form, that contains three repeating groups. Cyclic trimmer is a by-product found in all commercial polyester and results in deposit buildup in package-dyeing equipment. 

Other side chains include unusually long n-alkyl groups, - cyclics (cy-clolinear carbosiloxanes), fluorocarbons, phenylethenyl substituents, Cr-bound carbazole chromophores, and pendant bicyclic fragments. ... 

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