Search results
Results From The WOW.Com Content Network
2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (or DDQ) is the chemical reagent with formula C 6 Cl 2 (CN) 2 O 2. This oxidant is useful for the dehydrogenation of alcohols, [3] phenols, [4] and steroid ketones. [5] DDQ decomposes in water, but is stable in aqueous mineral acid. [6]
Orthogonal protection is a strategy allowing the specific deprotection of one protective group in a multiply-protected structure. For example, the amino acid tyrosine could be protected as a benzyl ester on the carboxyl group, a fluorenylmethylenoxy carbamate on the amine group, and a tert-butyl ether on the phenol
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Help; Learn to edit; Community portal; Recent changes; Upload file
For example, (C 6 H 5)(CH 3) 2 C + is referred to as a "benzylic" carbocation. The benzyl free radical has the formula C 6 H 5 CH 2 • . The benzyl cation or phenylcarbenium ion is the carbocation with formula C 6 H 5 CH + 2 ; the benzyl anion or phenylmethanide ion is the carbanion with the formula C 6 H 5 CH − 2 .
Figure 1. Cartoon representation (left) and a concrete example of a third generation dendronized polymer (right). The peripheral amine groups are modified by a substituent X which often is a protection group. Upon deprotection and modification substantial property changes can be achieved. The subscript n denotes the number of repeat units.
Sequential treatment with trimethylsilyl iodide then methanol can also be used for Boc deprotection, [7] [8] especially where other deprotection methods are too harsh for the substrate. [9] The mechanism involves silylation of the carbonyl oxygen and elimination of tert -butyl iodide ( 1 ), methanolysis of the silyl ester to the carbamic acid ...
The use of Fmoc as a temporary protecting group for amine at the N-terminus in solid phase synthesis is very widespread for Fmoc/tBu approach, because its removal with piperidine does not disturb the acid-labile linker between the peptide and the resin. [7]
A variety of approaches to protection and deprotection of carbonyls [6] including as dioxolanes [7] are known. For example, consider the compound methyl cyclohexanone-4-carboxylate, where lithium aluminium hydride reduction will produce 4-hydroxymethylcyclohexanol.