151132-35-3

Upstream product

• 577-19-5 2-nitrophenyl bromide 
• 29364-29-2 sodium tert-butyl thiolate 
• 609-73-4 o-nitroiodobenzene 
• 88-73-3 2-Chloronitrobenzene 
• 75-66-1 2-methylpropan-2-thiol 
• 1493-27-2 ortho-nitrofluorobenzene 

Downstream Products

• 885051-07-0 (R)-(+)-2-phenyl-2,3-dihydrobenzo[d]imidazo[2,1-b]thiazole 
• 1203507-02-1 (2S,3R)-3-isopropyl-2-phenyl-3,4-dihydro-2H-benzo[4,5]thiazolo[3,2-a]pyrimidine 
• 51942-41-7 o-aminophenyl tert-butyl sulfide 

Relevant academic research and scientific papers

Synthesis method of isothiourea catalyst

The invention relates to the field of organic chemistry, and in particular relates to a synthesis method of an isothiourea catalyst. The method comprises the following steps: (1) taking o-fluoronitrobenzene as an initial raw material to synthesize o-nitro

Thiol Anions in Nucleiphilic Aromatic Substitution Reactions with Activated Aryl Halides. Attack on Carbon vs Attack on Halogen

The reaction of o-iodonitrobenzene with thiol anions (RSNa, R = Me, 2-Pr, t-Bu) in 2-propanol solution produces the o-nitrophenyl thioether and nitrobenzene in relative proportions and with rates which depend on R.The results of kinetic analysis and of D-incorporation experiments are inconsistent with a radical chain mechanism as proposed earlier for the alkoxide-promoted hydro-de-halogenation of aryl halides.The data clearly indicate the involvement of a carbanionic intermediate (the o-nitrophenyl anion) and are consistent with a stepwise mechanism in which the first step is nucleophilic attack on iodine to form a sulphenyl halide and the o-nitrophenyl anion (a halogenophilic reaction).In contrast, the reaction of the other o-halonitrobenzenes (F, Cl, Br) produces exclusively the product of alkylthio-de-halogenation according to the addition/elimination (SNAr) mechanism.The fact that in these systems the reactivity of thiol anions results from their ability as bielectronic nucleophiles rather than as reducing agents is discussed.

Influence of Ion Pairing, Steric Effects, and Other Specific Interactions on the Reactivity of Thioanions with Chloronitrobenzenes. Nucleophilic Aromatic Substitution vs Reduction

The reactions in 2-propanol of the isomeric chloronitrobenzenes with thiolate nucleophiles, RS- (R=Me, i-Pr, t-Bu, Ph), have been studied to test for the ability of these representative thioanions of inducing chloride displacement and/or nitro reduction. m-Chloronitrobenzene gives a complex mixture of products, all still retaining the chlorine substituent, via redox processes involving nitro reduction and ring alkylthiolation.In contrast, the ortho and para isomers undergo substitution of chloride according to the addition/elimination SNAr mechanism also when O2 is removed from the reaction environment.Notably, treatment of o- and p-chloronitrobenzene with the oxanion 2-propoxide in oxygen-free i-PrOH results, instead, in nitro reduction.Kinetic and product studies indicate that i-PrS- is more reactive than i-PrO- in both redox and SNAr reactions, the difference in reactivity being, however, considerably greater in the latter process.The MeS- > i-PrS- > PhS- > t-BuS- reactivity order observed in the SNAr reactions is opposite, as far as the aliphatic thiolates are concerned, to the order of basicity.Notably, reactivity drops with increasing bulkiness of the attacking nucleophile.However, kinetic results obtained under conditions of ion paired and of "free" anions and the effects of ion pairing on the kortho/kpara ratios suggest that steric effects in the transition states are scarcely dependent on the bulkiness of the substituent R in the nucleophile RS- and that nucleophilic reactivity is largely determined by the extent of charge concentration on the attacking atom, which, in turn, affects the strength of ion-pairing interactions.