Research Aimed for the Development of Transition Metal Catalyzed Heterocyclic Synthesis.

本研究旨在利用过渡金属的氧化电位来开发氮氧杂环化合物的新合成方法。现将这3年来取得的成果总结如下。(1)对于钯（II）催化的烯烃胺化，脲用作特定的氨基亲核试剂（而不是氧亲核试剂），并且与迄今为止通常使用的磺酰胺和氨基甲酸酯相比显示出更高的反应性和多功能性。基于这种方法，可以非常有效地合成以下类别的化合物：顺式3-羟基吡咯烷-2-乙酸内酯（吡咯烷生物碱的通用合成中间体），双环二氢尿嘧啶，环脲，γ-和γ-氨基氨基酸。（2）钯催化3-丁炔-1-醇羰基化合成α-亚甲基-γ-丁内酯。产率高度依赖于碱的种类。环氧丙烷被证明是最好的碱。(3)2-芳基杂环（例如，2-芳基四氢呋喃，2-芳基哌啶）分别由高烯丙醇和高烯丙基胺与芳基三烷基锡的Pd（II）催化反应合成。

This research was aimed to develop new synthetic methodologies for nitrogen and oxygen heterocycles by the use of the oxidizing potential of transition metals. The results obtained in these 3 years are summarized as follows.(1) For the palladium(II) catalyzed amination of olefins, urea serves as a specific aminonucleophile (not an oxygen nucleophile) and shows the higher reactivity and versatility as compared with sulfonamide and carbamate, commonly utilized hitherto. Based on this methodology, the following classes of compounds can be synthesized very efficiently; cis 3-hydroxypyrrolidine-2-acetic acid lactones (versatile synthetic intermediates for pyrrolitidine alkaloid), bicyclic dihydrouracil, cyclic urea, gamm- and -amino amino acids. (2)alpha-Methylene-gamma-butyrolactones are synthesized by palladium(II) catalyzed carbonylation of 3-butyn-1-ols. The yields are highly dependent on the kind of bases. Propylene oxide proved to be the best base. (3) 2-Arylheterocycles (e.g., 2-aryltetrahydrofurans, 2-Arylpiperidines) are synthesized by the Pd(II)-catalyzed reaction of homoallyl alcohols and homoallylamines, respectively, with aryltrialkyltin.