Exploring the unique reactivities of heterobicyclic tetrazoles—access to functionally diverse and versatile heterocyclic scaffolds
作者:Stephen Hanessian、Benoît Deschênes-Simard、Daniel Simard
DOI:10.1016/j.tet.2009.06.033
日期:2009.8
tetrazoles such as (6R,8R)-(8-phenyl-5,6-dihydro-8H-tetrazolo[5,1-c][1,4]oxazin-6-yl)-alkanols (A, X=CH2OH) is highly acidic, being alkylated in preference to a hydroxymethyl group with NaH and active alkyl halides. The enantioenriched products B now contain a phenyl and alkyl group on a stereogenic benzylic carbon atom. The products are subject to β-elimination to give 1-1-[3-propenyl]-1H-tetrazol
氧杂双环四唑中的苄基氢原子,如(6 R,8 R)-(8-苯基-5,6-二氢-8 H-四唑[5,1- c ] [1,4]恶嗪-6-基) -链烷醇(A,X = CH 2 OH)是高度酸性的,优选被NaH和活性烷基卤化物烷基化为羟甲基。现在,对映体富集的产物B在立体异构的苄基碳原子上包含苯基和烷基。产物经β-消除,得到1- 1- [3- [丙烯基] -1H-四唑-5-基} -1-苯基-链烷醇。丙烯基链的裂解导致手性非外消旋的1-苯基-1-(1 H-四唑-5-基)-链烷醇C。氧杂双环四唑的自由基“异头”叠氮化,然后通过构型反转进行还原和闭环,生成氮杂双环四唑D,作为受限的官能化哌嗪。