Interpretation:
Propose the mechanism for the formation of
Concept introduction:
In the Merrifield solid-phase method, peptide synthesis is carried out with the growing amino acid chain covalently bonded to small beads of a
SN2 reaction is a type of reaction mechanism in which one bond is broken and one bond is formed simultaneously. In first step nucleophilic substitution reaction takes place. Since two reacting species are involved in the slow (rate-determining) step, this leads to the term substitution nucleophilic (bi-molecular) or SN2.
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Organic Chemistry
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- The formation of Br2 from NBS first involves the reaction of NBS with HBr to form an iminol intermediate and molecular bromine. The intermediate then undergoes acid-catalyzed tautomerism to form succinimide, the byproduct of the reaction. Propose a curved-arrow mechanism for the conversion of NBS into succinimide that also accounts for the formation of Br2.arrow_forwardPropose a synthesis of diethylstilbestrol (Problem 27-44) from phenol and any other organic compound required.arrow_forwardPh3P-CHCH3 H₂C H3C Aldehydes and ketones are converted into alkenes by means of a direct nucleophilic addition called the Wittig reaction. In the reaction, a triphenylphosphorine ylide, also called a phosphorane, adds to an aldehyde/ketone to give a four-membered cyclic intermediate called an oxaphosphetane. The oxaphosphetane is not isolated but instead spontaneously decomposes to release triphenylphosphine oxide and an alkene. CH3 00 + The ylide is formed by reaction of triphenylphosphine, a good nucleophile, with a primary alkyl halide in an SN2 reaction, followed by deprotonation of the carbon with a strong base, such as butyllithium. The carbonyl carbon and the carbon originally bonded to the halogen become the two carbons with the double bond in the product alkene X m CH3 The real value of the Wittig reaction lies in its ability to yield an alkene of predictable structure, as the C=C bond is precisely where the C=O bond was in the reactant and no isomers (other than E/Z isomers)…arrow_forward
- Draw a structural formula for the polymer formed in the following reactionsarrow_forwardIdentify the product CHICHINH, CH CH₂ CH2CH3 ON-Ethylpropanamide + propanoic acid ON,N-Diethylpropanamide + propanoic acid ON-Ethylethanamide + ethanoic acid ON,N-Diethylethanamide + ethanoic acidarrow_forwardPropose a synthesis for 3,5-dichloro-2-methoxybenzoic acid starting from phenol.arrow_forward
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