The Research On ?-acryloyloxylation And ?-phthalimidoxylation Of Ketones

The a-H functionalization of ketones as one of the most important reaction in organic chemistry has attracted much attention by researchers.a-Acryloyloxyketones and a-phthalimidoxyketones,as significant intermediates in organic synthesis and medical chemistry,have drawn more and more attention by scientists.Nevertheless,although great contributions have been made by researchers,there are still some problems need to be solved.The a-acryloyloxylation of ketones still face the problems of low productivity,harsh reaction conditions and poor applicability of substrates.The a-phthalimidoxylation of ketones used plenty of transition-metal which would damage the environment.And there remain lack approach in direct a-phthalimidoxylation of ketones with N-hydroxyphthalimide.Therefore,it is still important to develop new methods to synthesis a-acryloyloxyketones and a-phthalimidoxyketones.In this paper,we developed and studied the a-acryloyloxylation of ketones and the a-phthalimidoxylation of ketones.The main researches are as follows:(1)The a-acryloyloxylation of ketones and a-phthalimidoxylation of ketones were summarized.Based on the results,we expounded the purpose,significance,and primary coverage of this research.(2)A systematic study for a-acryloyloxylation of ketones was made.Firstly,we use propiophenone and cinnamic acid as the model substrates to optimize the reaction conditions.And the optimized reaction conditions were:propiophenone(0.5 mmol),cinnamic acid(1.0 equiv),CuI(20 mol%),di-t-butyl peroxide(2.0 equiv),TEAB(10 mol%),DMSO(2.0 mL),100?,12 h.After optimized the reaction conditions,the scope of substrates were examined.The results show that this reaction system has a good applicability for both ketones and ?,?-unsaturated carboxylic acids.Then,we also tested various types of carboxylic acids.It was found that benzoic acid and phenylglyoxylic acid reacted well at this condition.However,when phenylpropiolic acid was used as the substrate,a decarboxylation-coupling compound was obtained instead of the target product.Finally,several control experiments were carried out in order to have a correct knowledge of the reaction,a plausible reaction mechanism was proposed based on the experiments results and reported literatures.(3)A systematic study for a-phthalimidoxylation of ketones was explored.Different factors were tested and the optimized reaction conditions were obtained through using propiophenone and NHPI as substrates:propiophenone(0.5 mmol),NHPI(2.0 equiv),K2S2O8(2.0 equiv),TBAI(10 mol%),C1CH2CH2Cl(2.0 mL),100?,12 h.After optimizing the reaction conditions,we explored the scopes of substrates for the reaction.It was found that aromatic ketones and heterocyclic ketones both reacted well at this system.However,aliphatic ketones could not react in the reaction.Finally,a possible mechanism was proposed based on the control experiments and related literature reports.