Abnormal Behaviour of Allenylsulfones under Lu’s Reaction Conditions: Synthesis of Enantiopure Polyfunctionalised Cyclopentenes
作者:Alberto Núñez、M. Rosario Martín、Alberto Fraile、José L. García Ruano
DOI:10.1002/chem.200903185
日期:2010.5.10
adducts in good yields. Allenylsulfones evolve through a different mechanism to that proposed for allenoates (Lu’s reaction) and afford bicyclic adducts in which the sulfonyl group is joined to C‐5. This has advantages on the stereochemical control of further reactions leading to enantiomerically pure polyfunctionalised cyclopentenes and cyclopentanes.
正式[3 + 2] 5- alkoxyfuran-2(5的环加成ħ) -酮1和2与allenylsulfones 3 - 5,由亲核试剂不同促进,得到3-烷氧基-5-芳基磺酰基- 3,3,6,6 a-四氢-1 H-环戊[ c[呋喃-1]的收率高,并且可以完全控制区域和π面选择性。在呋喃酮环上引入亚磺酰基可提高呋喃酮的反应性,并可以高收率合成光学纯的双环加合物。烯丙基砜是通过与提议的烯丙酸酯不同的机理演化出来的(卢氏反应),并提供双环加合物,其中磺酰基连接到C-5上。这在立体化学控制进一步的反应上具有优势,所述反应进一步导致对映体纯的多官能化的环戊烯和环戊烷。