Alkylthioether synthesis via imidazole mediated mitsunobu condensation

Recent Advances in the Mitsunobu Reaction: Modified Reagents and the Quest for Chromatography‐Free Separation

“…[22] Imidazole improves the yields for the synthesis of alkylthioethers in the presence of Me 3 P and ADDP 4g. [43] The addition of zinc bis(N,N-dimethylthiocarbamate) [(Me 2 NCOS) 2 Zn, Ziram] in toluene to a classical mixture of Ph 3 P and DEAD allows for the conversion of 1,2-disubstituted 1,3-diols to corresponding oxetanes. The starting 1,3-diols can contain a tertiary phenylsulfanyl, phenylsulfonyl, or tert-butyl group adjacent to the secondary hydroxyl group.…”

Triphenylphosphonium Anhydride Trifluoromethanesulfonate

“…The Mitsunobu combination of Triphenylphosphine and Diethyl Azodicarboxylate is a well-established system for the conversion of primary and secondary alcohols into good leaving groups, for subsequent displacement by a variety of acidic pronucleophiles (e.g., carboxylic acids, phenols, thiols, Sodium Azide, and potassium phthalimide). 33, 34 In contrast, though the Hendrickson reagent is believed to operate via the same reactive intermediate, the spectrum of activity is different from that observed in the Mitsunobu reaction. 30 Though substitution by various nucleophiles has been reported for primary alcohols, secondary alcohols tend to undergo elimination rather than substitution (see above).…”

The Choice of Phosphane Reagent in Fukuyama−Mitsunobu Alkylation: Intramolecular Selectivity Between Primary and Secondary Alcohols in the Preparation of Asymmetric Tetraamine Building Blocks for Synthesis of Philanthotoxins

“…The more recently described Tsunoda conditions, employing tributylphosphane (TBP) and 1,1Ј-(azodicarbonyl)dipiperidide (ADDP), [29] were reported to give excellent yields in the alkylation of 2-nitrobenzenesulfonamides in the synthesis of polyamine toxins on solid phase. [30] Consequently, this reagent combination was selected, along with the less hindered N,N,NЈ,NЈ-tetramethylazodicarboxamide (TMAD) [31] and trimethylphosphane (TMP) [32,33] for our investigation of the alkylation of 2-nitrobenzenesulfonamides (Ns-amides) with secondary alcohols. The Ns group is convenient in both solid and solution phase syntheses, because it is readily removed under mild conditions.…”