Chemie polyfunktioneller Moleküle, 80 [1]. Kristall- und Molekülstrukturen der Heteronoradamantane 5-Methyl-2.2.8.8-tetra-ethoxycarbonyl-1.3.7-triarsa-tricyclo[3.3.1.0^3,7]nonan und 5-Methyl-1.3.7-triarsa-2.8-diselena-tricyclo[3.3.1.0^3,7]nonan / Chemistry of Polyfunctional Molecules, 80 [1]. Crystal and Molecular Structures of the Heteronoradam antanes 5-Methyl-2.2.8.8-tetra-ethoxycarbonyl-1.3.7-triarsa-tricyclo[3.3.1.0^3,7]nonane and 5-M ethyl-1.3.7-triarsa-2.8-diselena-[3.3.1.0^3,7]nonane

Abstract

The molecular and crystal structures of the nor-heteroadam antanes CH 3 C(CH 2 As) 3 [C(COOCH 2 CH 3 ) 2 ] 2 (1) and CH 3 C(CH 2 As) 3 Se 2 (2) have been investigated in order to obtain confirmation of the rare structures deduced earlier from mass, 1 H NMR and vibrational spectroscopy. Crystals of 1 are triclinic, space group P1̄-C 1 i with a - 769.27(30), b = 1036.09(14), c = 1599.18(17) pm, α = 98.236(10)°, β = 97.987(18)°, γ = 103.633(20)° and Z = 2. On the basis of 1821 unique reflections the structure was refined to a weighted R value of 5.28%. The crystals of 2 are monoclinic, space group P 2 1 /c-C 5 2h with a = 1102.73(23), b - 727.49(14), c = 1281.27(42) pm. β = 98.803(21)° and Z = 4. On the basis of 1065 unique reflections the structure was refined to a weighted R value of 5.93%. Several attempts to synthesize CH 3 C(CH 2 As) 3 Te 2 failed.