118958-19-3Relevant academic research and scientific papers
THE MANNICH CONDENSATION WITH 1-HETERA-4-CYCLOHEXANONES. THE NOVEL FORMATION OF 7-BENZYL-3-HETERA-7-AZABICYCLONONAN-9-ONES, 3,6-DIBENZYLHEXAHYDRO-8a-METHOXY 5H-4a,8-(METHANOHETERAMETHANO)-2H-PYRIDO-1,3-OXAZINES, AND 2,4,10,12-TETRABENZYL-2,4,10,12-TETRAAZA-15-HETERADISPI...
Smith, Gary S.,Berlin, K. Darrell,Zisman, Stan A.,Holt, Elizabeth M.,Green, Vicki A.,Helm, Dick Van Der
, p. 91 - 112 (2007/10/02)
We report for the first time the formation of unusual multicyclic products from the condensation of 1-hetera-4-cyclohexanones in a Mannich reaction with benzylamine, formaldehyde, and acetic acid in methanol.In addition to the expected ketones, namely 7-benzyl-3-hetera-7-azabicyclononan-9-ones, there were obtained from 4-thianone and 4-selenanone the following systems.Repeated Mannich condensations produced 3,6-dibenzylhexahydro-8a-(methoxy-5H-4a,8-(methanothiomethano)-2H-pyrido-1,3-oxazine, 3,6-dibenzylhexahydro-8a-methoxy-5H-4a,8-(methanoselenomethano)-2H-pyrido-1,3-oxazine, 2,4,10,12-tetrabenzyl-2,4,10,12-tetraaza-15-thiadispiro-hexadecan-7-one, and 2,4,10,12-tetrabenzyl-2,4,10,12-tetraza-15-selenadispirohexadecan-7-one.Single crystal X-ray diffraction analysis confirmed the structures of the first three solids.Using tetrahydro-4H-pyran-4-one, it was possible to obtain 7-benzyl-3-oxa-7-azabicyclononan-9-one and 2,4,10,12-tetrabenzyl-2,4,10,12-tetraaza-15-oxadispirohexadecan-7-one.To the best of our knowledge, these systems have not been previously recorded, and the method reported herein is a one-step approach.NMR analyses, including 1H, 13C, and 15N analyses, were completed and support all of the structures described herein.A mechanism is briefly outlined to explain the formation of these novel polycyclic heterocycles. - Key words: Mannich reaction; 1-hetera-4-cyclohexanones; 3,6-dibenzylhexahydro-8a-methoxy-5H-4a,8-(methanoheteromethano)-2H-pyrido--1,3-oxazine; 2,4,10,12-tetrabenzyl-2,4,10,12-tetraaza-15-heteradispirohexadecan-7-one; 7-benzyl-3-hetera-7-azabicyclononan-9-ones; selenium and sulfur derivatives.
