Conformational analysis of 3-borabicyclo[3.3.1]nonane derivatives
作者:M.E. Gursky、A.S. Shashkov、B.M. Mikhailov
DOI:10.1016/s0022-328x(00)83850-4
日期:——
Conformations of 3-borabicyclo[3.3.1]nonane derivatives have been studied by means of 1H and 13C NMR spectroscopy. With the aid of the coupling constants 3J(HH) and 13C chemical shifts it has been shown that all the derivatives of 3-borabicyclo[3.3.1]nonane with the trigonal boron atom studied are in a flattened double-chair conformation. In 3-borabicyclo[3.3.1]nonane derivatives with the tetra-coordinated
已通过1 H和13 C NMR光谱研究了3-borabicyclo [3.3.1]壬烷衍生物的构象。借助偶合常数3 J(HH)和13 C化学位移,研究表明,所研究的3-borabicyclo [3.3.1]壬烷与三角硼原子的所有衍生物均呈扁平双椅构型。在具有四配位的硼原子和7α-位取代基的3-borabicyclo [3.3.1]壬烷衍生物中,椅子-舟子构象占优势,舟子构象是环己烷环的特征。唯一的例外是硼原子与7α取代基之间具有内部供体-受体键的化合物。
synthesis of bicyclo[3.3.1]nonane compounds via allylboron/acetylene condensation has been worked out. The carbonylation-oxidation of 3-methyl-3-borabicyclo[3.3.1]non-6-ene(I) results in the formation of 3α-hydroxy-3β-methylbicyclo[3.3.1]non-6-ene (IVa) and its 3β-hydroxy-3α-methyl isomer (IVb). Similar treatment of 3-methyl-3-borabicyclo[3.3.1]nonane (II) gives 3α-hydroxy-3β-methylbicyclo[3.3.1]nonane (VIIa)