Lynch V M, Liao Y, Martin S F, Davis B E
Department of Chemistry and Biochemistry, University of Texas, Austin 78712.
Acta Crystallogr C. 1992 Sep 15;48 ( Pt 9):1703-5. doi: 10.1107/s0108270192001045.
(4a alpha,7a beta,10a beta)-2-Benzyl-1,2,3,4,4a,7,7a,8,9,10-decahydro-8,8- dimethylpyrrolo[2,3-i]isoquinolinium iodide, C20H29N2+.I-, M(r) = 424.37, monoclinic, P2(1)/n, a = 9.441 (4), b = 10.378 (4), c = 20.023 (9) A, beta = 91.56 (3) degrees, V = 1961 (1) A3, Z = 4, Dx = 1.44 g cm-3 (188 K), lambda(Mo K alpha) = 0.7107 A, mu = 16.16 cm-1, F(000) = 864, T = 188 K, R = 0.0288 for 3070 reflections [Fo greater than or equal to 4 sigma(Fo)]. The crystal structure determination was undertaken in order to establish the configuration around C10a. The rings of the isoquinoline group are trans, with the pyrrole moiety cis fused. The A ring is in the chair conformation, while the cyclohexene ring, B, is in the boat conformation owing to the cis fusion of the five-membered pyrrole ring. The pyrrole ring, C, assumes the half-chair conformation. The C-N bonds of the quaternary N atom, N8, are longer than those of the tertiary N atom, N2 [1.517 (2) for N8 and 1.463 (2) A for N2].
（4aα，7aβ，10aβ）-2-苄基-1,2,3,4,4a,7,7a,8,9,10-十氢-8,8-二甲基吡咯并[2,3-i]异喹啉碘化物，C20H29N2⁺·I⁻，M(r)=424.37，单斜晶系，P2(1)/n，a = 9.441(4)，b = 10.378(4)，c = 20.023(9) Å，β = 91.56(3)°，V = 1961(1) ų，Z = 4，Dx = 1.44 g cm⁻³(188 K)，λ(Mo Kα)=0.7107 Å，μ = 16.16 cm⁻¹，F(000)=864，T = 188 K，对于3070个反射[Fo≥4σ(Fo)]，R = 0.0288。进行晶体结构测定以确定C10a周围的构型。异喹啉基团的环是反式的，吡咯部分是顺式稠合的。A环呈椅式构象，而环己烯环B由于五元吡咯环的顺式稠合而呈船式构象。吡咯环C呈半椅式构象。季铵氮原子N8的C-N键比叔氮原子N2的C-N键长[N8为1.517(2) Å，N2为1.463(2) Å]。
