On October 31, 2015, Stead, Darren; O’Brien, Peter; Sanderson, Adam published an article.Name: tert-Butyl 7-benzyl-9-oxo-3,7-diazabicyclo[3.3.1]nonane-3-carboxylate The title of the article was Investigation of the Lithiation-Trapping of an N-BOC Bispidine-Ketal: Reactivity and Diastereoselectivity. And the article contained the following:
The lithiation-trapping of an N-BOC bispidine-ketal using BuLi/TMEDA has been studied. Key findings include an activating effect of the 4-ketal group on the lithiation and complete diastereoselectivity with methylation and Cu-mediated allylation. In contrast, reduced diastereoselectivity was noted for direct allylation and silylation; mechanistic explanations are proposed. The synthesis of the target compounds was achieved using 7-(phenylmethyl)-3,7-diazabicyclo[3.3.1]nonane-3-carboxylic acid 1,1-dimethylethyl ester (i.e., a bispidine carboxylic acid ester derivative), 9-oxo-7-(phenylmethyl)-3,7-diazabicyclo[3.3.1]nonane-3-carboxylic acid 1,1-dimethylethyl ester (i.e., a bispidine-ketone derivative), 7-(phenylmethyl)Spiro[3,7-diazabicyclo[3.3.1]nonane-9,2′-[1,3]dioxolane]-3-carboxylic acid 1,1-dimethylethyl ester (i.e., a cyclic-ketal-bispidine derivative) as starting materials. The title compounds thus formed included bispidine-diastereomer derivatives, such as (1R,2S,5S)-rel-7-(phenylmethyl)-2-(2-propen-1-yl)-3,7-diazabicyclo[3.3.1]nonane-3-carboxylic acid 1,1-dimethylethyl ester. The experimental process involved the reaction of tert-Butyl 7-benzyl-9-oxo-3,7-diazabicyclo[3.3.1]nonane-3-carboxylate(cas: 227940-70-7).Name: tert-Butyl 7-benzyl-9-oxo-3,7-diazabicyclo[3.3.1]nonane-3-carboxylate
The Article related to lithiation bispidine ketal diastereoselectivity, Heterocyclic Compounds (More Than One Hetero Atom): Eight- and Higher-Membered Rings and other aspects.Name: tert-Butyl 7-benzyl-9-oxo-3,7-diazabicyclo[3.3.1]nonane-3-carboxylate
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