Structures of pyrrolo-1,3-heterocycles prepared from 3-aroylpropionic acid and cyclic aminoalcohols: an NMR and X-ray diffraction study
作者:Petri Tähtinen、Reijo Sillanpää、Géza Stá、Angela E. Szabó、Kalevi Pihlaja
DOI:10.1039/a604905b
日期:——
By the reaction of 3-(4-chlorobenzoyl)propionic acid 1
with 1,2- and 1,3-bifunctional compounds, new condensed
heterocycles have been prepared. Thus, the reaction of 1 with
hydrazine gave the pyridazin-3-one 2 and with ethylenediamine,
the pyrrolo[1,2-a]imidazole 3 was formed. Reaction of
compound 1 and 2-aminoethanol yielded the
pyrrolo[2,1-b]oxazolidinone 4 and the reaction with
3-aminopropan-1-ol resulted in the
pyrrolo[2,1-b][1,3]oxazinone 5. With
o-aminothiophenol tricyclic
pyrrolo[2,1-b]benzothiazolone 6 was prepared. In
comparison with 4–6, the structure of the new tri- and
tetra-cyclic compounds 7–14 are discussed. With the
starting oxoacid 1, the cyclic and bicyclic aminoalcohols gave
the following fused heterocycles: cis- and
trans-2-(hydroxymethyl)cyclohexane- and
cyclohex-4-ene-amines yielded
pyrrolo[1,2-a][3,1]benzoxazinones 7–10,
diexo-3-(hydroxymethyl)bicyclo[2.2.1]heptane-2-amine and
hept-5-ene-2-amine yielded the diexo (11 and 12) and
diendo (13 and 14) methylene-bridged
pyrrolo[1,2-a][3,1]benzoxazinones. The structures of the
compounds were proved by 1D 1H and 13C NMR
spectroscopy, NOE difference spectroscopy and several different
homo- and hetero-nuclear multipulse techniques (COSY, NOESY,
HETCOR). The 1D 1H NMR spectra were analysed by
iterative spin-simulation using PERCH-software. Many interesting
long-range couplings were found. Some aid for structural
elucidation was gained from molecular modelling calculations. The
crystal structures of 7, 9–11, 13 and 14 elucidated from
the X-ray diffraction measurements do not differ significantly
from the solution structures.
通过3-(4-氯苯甲酰)丙酸1与1,2-和1,3-双官能团化合物的反应,制备了新的稠合杂环化合物。因此,1与肼反应得到吡嗪-3-酮2,与乙二胺反应形成吡咯[1,2-a]咪唑3。化合物1与2-氨基乙醇反应生成吡咯[2,1-b]噁唑啉酮4,与3-氨基丙醇-1反应生成吡咯[2,1-b][1,3]噁嗪酮5。与邻氨基硫酚反应制备了三环的吡咯[2,1-b]苯并噻唑酮6。与4-6相比,新型的三环和四环化合物7-14的结构被讨论。以起始的酮酸1,环状和双环的氨基醇生成了以下稠合杂环:顺式和反式2-(羟甲基)环己烷和环己-4-烯胺生成吡咯[1,2-a][3,1]苯并噁嗪酮7-10,双环[2.2.1]庚烷-3-(羟甲基)-2-胺和庚-5-烯-2-胺生成双环(11和12)和双内(13和14)亚甲基桥联的吡咯[1,2-a][3,1]苯并噁嗪酮。这些化合物的结构通过1D 1H和13C NMR光谱、NOE差谱及多种同核和异核多脉冲技术(COSY, NOESY, HETCOR)得到证实。1D 1H NMR光谱通过PERCH软件迭代自旋模拟进行分析。发现了许多有趣的长程偶合。分子建模计算提供了一些结构阐明的辅助。从X射线衍射测量的晶体结构7, 9-11, 13和14与溶液结构没有显著差异。