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  2. 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone - Wikipedia

    en.wikipedia.org/wiki/2,3-Dichloro-5,6-dicyano-1...

    Synthesis of DDQ involves cyanation of chloranil. J. Thiele and F. Günther first reported a 6-step preparation in 1906. [7] The substance did not receive interest until its potential as a dehydrogenation agent was discovered. A single-step chlorination from 2,3-dicyanohydroquinone was reported in 1965. [8]

  3. File:PMB deprotection mechanismn.svg - Wikipedia

    en.wikipedia.org/wiki/File:PMB_deprotection...

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  4. Protecting group - Wikipedia

    en.wikipedia.org/wiki/Protecting_group

    The use of protective groups is pervasive but not without criticism. [103] In practical terms their use adds two steps (protection-deprotection sequence) to a synthesis, either or both of which can dramatically lower chemical yield. Crucially, added complexity impedes the use of synthetic total synthesis in drug discovery.

  5. File:PMB deprotection.svg - Wikipedia

    en.wikipedia.org/wiki/File:PMB_deprotection.svg

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  6. Fluorenylmethyloxycarbonyl protecting group - Wikipedia

    en.wikipedia.org/wiki/Fluorenylmethyloxycarbonyl...

    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]

  7. Desulfonylation reactions - Wikipedia

    en.wikipedia.org/wiki/Desulfonylation_reactions

    The sulfonyl functional group (RS(O) 2 R') has become an important electron-withdrawing group for modern organic chemistry. α-Sulfonyl carbanions may be used as nucleophiles in alkylation reactions, Michael-type additions, and other processes. [3] After having served their synthetic purpose, sulfonyl groups are often removed.

  8. Photolabile protecting group - Wikipedia

    en.wikipedia.org/wiki/Photolabile_protecting_group

    The first reported use of a PPG in the scientific literature was by Barltrop and Schofield, who in 1962 used 253.7 nm light to release glycine from N-benzylglycine. [4] Following this initial report, the field rapidly expanded throughout the 1970s as Kaplan [6] and Epstein [7] studied PPGs in a variety of biochemical systems. During this time ...

  9. Photoredox catalysis - Wikipedia

    en.wikipedia.org/wiki/Photoredox_catalysis

    Typically, selective cleavage of a PMB ether in the presence of a benzyl ether uses strong stoichiometric oxidants such as 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) or ceric ammonium nitrate (CAN). PMB ethers are far more susceptible to oxidation than benzyl ethers since they are more electron-rich.