[3 + 2] Cycloaddition Reaction of in Situ Formed Azaoxyallyl Cations with Aldehydes: An Approach to Oxazolidin-4-ones
作者:Kaifan Zhang、Chi Yang、Hequan Yao、Aijun Lin
DOI:10.1021/acs.orglett.6b02254
日期:2016.9.16
A novel [3 + 2] cycloaddition reaction between in situ formed azaoxyallyl cations and aldehydes has been developed. This concise method allows the rapid formation of a number of oxazolidin-4-ones in high yields with good functional group tolerance at room temperature. Further transformation and late-stage modifications of drug molecules could also be achieved in good yields, highlighting the potential
A novel [3 + 2] cycloaddition reaction of azaoxyallyl cations and aromatic ethylenes has been developed to afford multi-substituted pyrrolidinones in moderate to good yields. This method not only further expands the synthetic utility of α-halo hydroxamates, but also provides an alternative method for the synthesis of bioactive molecules containing pyrrolidinones.
Synthesis of 2-Aminoimidazolones and Imidazolones by (3 + 2) Annulation of Azaoxyallyl Cations
作者:Maria C. DiPoto、Jimmy Wu
DOI:10.1021/acs.orglett.7b03719
日期:2018.2.2
The first examples of (3 + 2) annulations between azaoxyallyl cations and cyanamides and nitriles to give the corresponding 2-aminoimidazolones and imidazolones are reported. On the basis of the isolation of unexpected imidate products with certain substrates, it is proposed that the reaction proceeds via fast kinetic O-alkylation followed by rearrangement to the thermodynamically favored 2-aminoimidazolones
A highly efficient one-pot synthesis of thiazolidin-4-ones via [3+2] cycloaddition of aza-oxyallylic cations with isothiocyanates is developed. The aza-oxyallyic cations were generated in situ in the present of a base. This cycloadditionreaction allows the rapid access to a variety of thiazolidin-4-one derivatives in mild conditions, good yield, and excellent functional group compatibility.
1,2,4-Oxadiazin-5-ones were prepared via [3+3] cycloaddition of in situ generated aza-oxyallylic cations with nitrile oxides in good yields and excellent functional group compatibility. This efficient transformation is metal-free and is promoted by an inorganic base Cs2CO3. In addition, this reaction features simple-operation, mild conditions, and high regioselectivity.
1,2,4-Oxadiazin-5-ones是通过[3 + 3]环合成原位生成的氮杂-氧烯丙基阳离子与腈氧化物而制备的,具有良好的收率和出色的官能团相容性。这种有效的转变是无金属的,并由无机碱Cs 2 CO 3促进。另外,该反应具有操作简单,条件温和和区域选择性高的特征。