2-Pyridinesulfenyl chloride

The Npys group can be. cleaved reductively with BU3P, H2O or mercaptoethanol. It is stable to CF3COOH (24 h), 4 M HCl/dioxane (24 h), and HF (1 h). The related reagent, 2-pyridinesulfenyl chloride, has also been proposed as a useful reagent for the deprotection of the 5-trityl, 5-diphenylmethyl, 5-acetamidomethyl, 5-/-butyl, and S-r-butylsulfenyl groups, but this reagent is very susceptible to hydrolysis. ... 

Nitro-2-pyridinesulfenyl chloride [68206-45-1 ] M 190.2, m 217-222 (dec). Crystallises as yellow needles from CH2CI2. When pure it is stable for several weeks at room temperature, and no decomposition was observed after 6 months at <0°. UV (MeCN) has Xmax at 231nm (e 12,988), 264nm (e 5,784) and 372nm (e 3,117). [NMR and UV Matsuda and Aiba Chem Lett 951 1978 Wagner et al. Chem Ber 75 935 1942.]... 

Treatment of 3-nitro-2-pyridinesulfenyl chloride with alcohols gives 3-nitro-2-pyridinesulfenates (Scheme 128) which have been used for peptide protection <81H(15)1089). 

During a synthesis of the antibiotic Micacocidin, a p-methoxybenzyl group was used to protect the thiol function in intermediate 8.1 [Scheme 5.8].22 The 5-p-methoxybenzyl group was cleaved in two steps by first reacting 8.1 with 3-nitro-2-pyridinesulfenyl chloride (83) to give the disulfide intermediate 83 which was then treated with tributylphosphine in aqueous acetone to afford the thiol 8.4 in 69% overall yield for the two steps 2324... 

Nitrocyclopentene, 164, 165 Nitromercuration, 292-293 Nitromethane, 323 Nitromethylation, 323 Nitronium tetrafluoroborate, 324 Nitroperbenzoic acid, 324 p-Nitrophenyl selenocyanate, 325 o-Nitrophenyl thiocyanate, 325 3-Nitro-2-pyridinesulfenyl chloride, 325-326... 

Nitro-2-pyridinesulfenyl chloride, CH2CI2, 0°C, 30min then BU3P, 69%... 

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