Study On Synthesis Of3-Brom-1-(3-Chloro-2-Pyridinyl)-3-Pyrazolidinecarboxy And T-Butyl Hydroxy Anisole

3-Brom-1-(3-chloro-2-pyridinyl)-3-pyrazolidinecarboxy is an importantintermediate for synthesis Rynaxypyr,which is a new Ryanodine Receptor inhibitorpecticide.This paper reported the synthesis of the literature of theintermediate,compared with advantages and disadvantages of these synthesismethods,and proposed a more reasonable synthetic route.First,2,3-dichloropyridinewas synthesized from3-aminopyridine by substitution and diazotization,and thenreacted with hydrazine to give3-chloro-2-hydrazinopyridine.Then,3-chloro-2-hydrazinopyridine reacted with diethyl maleate to give2-(3-chloro-3-pyridinyl)-5-oxo-3-pyrazolidenecarboxylate by cyclization.Finally,target molecular3-brom-1-(3-chloro-2-pyridinyl)-3-pyrazolidinecarboxy can be obtained throughaddition reaction,eliminate reaction and hydrolysis reaction.And the totle yield was34.36%.Tert-Butyl Hydroxy Anisole is a good anti-oxidant.It has widely used forfood,medicine and others to anti-oxidate.This paper proposed a more appropriatesynthesis method through theoretical analysis of the molecular structure oftert-butyl hydroxyl anisole,and reported the synthesis methods of the literature.Tert-butyl hydroxyl anisole was synthesized from4-methoxyphenol,by methylteriary butyl ether alkylation and sulfuric acid catalyst.This paper optimized thesynthetic processes,and explored selectivity of the reaction,and gained criticalconditions for the selective control,which were materials ratio n(4-methoxyphenol):n(methyl teriary butyl ether):n(sulfuric acid)=2:1:1,reaction temperature100℃,reaction time4h.And the yield was17%.The product obtained in this paper are by IR and1HNMR to determine itsstructure.