- Synthesis of Amines and Amino Alcohols by Electrophilic Amination and Highly Stereoselective Reduction
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A practical and selective method for the synthesis of the β-arylamines 5 and the cis- or trans-amino alcohols 8 and 11 is reported.The reaction sequence starts from α-tetralones 1 which readily react with dibenzyl azodicarboxylate to afford the protected α-hydrazino ketones 2.Then, depending on the reduction conditions, the trans-hydrazino alcohols 10 or the cis isomers 7 are formed predominantly.The stereoselectivities which range between 18:1 and 1:67 (trans/cis) are explained by stereoelectronic effects (?,?* interactions) and steric hindrance.Depending on the workup procedure, we can control, whether the cis-hydrazino alcohols 7 or the oxazolidinone derivatives 3 are isolated.Subsequent hydrogenolyses of 4, 7 and 10 lead to the target molecules 5, 8 and 11, respectively. Key Words: Electrophilic amination / Dibenzyl azodicarboxylate / Stereoselective reduction
- Gmeiner, Peter,Bollinger, Bernd
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p. 273 - 278
(2007/10/02)
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- Efficient Methodology for the Preparation of β-Aminotetralin Derivatives via Electrophilic Amination
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A mild and efficient method for the construction of β-aryl amines from the corresponding α-aryl ketones is presented.The key step of the synthesis involve an electrophilic amination by dibenzyl azodicarboxylate followed by a stereoselective LiHBEt3 reduction.The reaction sequence is applied to the synthesis of the tricyclic ergoline analogue 4. Key words: electrophilic amination; stereoselective reduction; α-amino ketones.
- Gmeiner, Peter,Bollinger, Bernd
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p. 5927 - 5930
(2007/10/02)
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