Woo Kyoungja, G. Carpenter, D. A. Sweigart
Jun 1, 1994
Citations
0
Influential Citations
18
Citations
Journal
Inorganica Chimica Acta
Abstract
Abstract Treatment of the A-ring aromatic steroids estrone 3-methyl ether and β-estradiol 3, 17-dimethyl ether with Mn(CO) 5 + BF 4 − in CH 2 Cl 2 yields the corresponding [(steroid)Mn(CO) 3 ]BF 4 salts 1 and 2 as mixtures of α and β isomers. The X-ray structure of [(estrone 3-methyl ether)Mn(CO) 3 ]BF 4 · CH 2 Cl 2 ( 1 ) having the Mn(CO) 3 moiety on the α side of the steroid is reported: space group P 2 1 with a =10.3958(9), b =10.9020(6), c =12.6848(9) A, β=111.857(6)°, Z =2, V =1334.3(2) A 3 , ϱ calc =.481 cm −3 , R =0.0508, and wR =0.0635. The molecule has the traditional ‘piano stool’ structure with a planar arene ring and linear MnCO linkages. The nucleophiles NaBH 4 and LiCH 2 C(O)CMe 3 add to [(β-estradiol 3,17-dimethyl ether)Mn(CO) 3 ]BF 4 ( 2 ) in high yield to give the corresponding α- and β-cyclohexadienyl manganese tricarbonyl complexes ( 3 ). The nucleophiles add meta to the arene -OMe substituent and exo to the metal. The α and β isomers of 3 were separated by fractional crystallization and the X-ray structure of the β isomer with an exo -CH 2 C(O)CMe 3 substituent is reported (complex 4 ): space group P 2 1 2 1 2 1 with a =7.5154(8), b =15.160(2), c =25.230(3) A, Z =4, V =2874.4(5) A 3 , ϱ calc =1.244 g cm −3 , R =0.0529 and wR 2=0.1176. The molecule 4 has a planar set of dienyl carbon atoms with the saturated C(1) carbon being 0.592 A out of the plane away from the metal. The results suggest that the manganese-mediated functionalization of aromatic steroids is a viable synthetic procedure with a range of nucleophiles of varying strengths.