CAS: 495-20-5; Conhydrine

📜1-Boc-哌啶置于四甲基乙二胺,仲丁基锂体系中,化学反应 0.33H,反应生成 羟毒芹碱
参考文献:.Alpha.-Lithioamine Synthetic Equivalents: Syntheses Of Diastereoisomers From Boc Derivatives Of Cyclic Amines
标题:.Alpha.-Lithioamine Synthetic Equivalents: Syntheses Of Diastereoisomers From Boc Derivatives Of Cyclic Amines
摘要:Sequences Of Alpha'-Lithiations And Electrophilic Substitutions Of Boc-Pyrrolidines,Boc-Piperidines,And Boc-Hexahydroazepines That Provide Compounds Which Are Substituted Adjacent To Nitrogen Are Reported,And The Pathways Of The Reactions Are Discussed. By This Methodology Monosubstituted 2 And Disubstituted 2,4,2,6,And 2,5 Boc-Piperidines Are Obtained As Single Or Separable Diastereoisomers Consistent With Equatorial Lithiations And Retentive Electrophilic Substitution In Chair Conformations. Both Cis And Trans 2,6-Disubstituted Diastereoisomers Can Be Prepared,And Control Of Diastereoselectivity Is Demonstrated By Syntheses Of Solenopsin A,A 2,6-Trans-Disubstituted Piperidine,And Of Boc-Dihydropinidine,A 2,6-Cis-Disubstituted Piperidine. In The Case Of 3-Methoxy-Boc-Piperidine Elimination Of Methoxide occurs Upon Lithiation,And With Cis-2,4-Disubstituted Boc-Piperidines The Electrophile Is Introduced With Trans Stereochemistry At C-6. These Reactions Are Suggested To Involve Twist Boat Conformations Consistent With An X-Ray Crystal Structure Of 2-Methyl-6-(Trimethylstannyl)-4-Phenyl-N-Boc-Piperidine. Boc-Pyrrolidine Lithiates More Rapidly Than Boc-Piperidine,Provides 2-Substituted Products With Electrophiles,And On Further Lithiation-Substitution Gives 2,5-Cis-And-Trans-Substituted Products. Boc-Perhydroazepine Provides 2-Substituted Products By The Sequence And On Further Lithiation-Substitution Gives 2,7-Trans-Disubstituted Products.
DOI:10.1021/jo00057A024