A procedure for the synthesis of tertiary amines via reductiveamination of aldehydes with molecular hydrogen as a reducing agent using homogeneous rhodium catalysis is presented. Using an amine to aldehyde ratio of 4/1 enabled the synthesis of tertiary amines from nine different aldehydes and nine different secondary amines with selectivities up to 99% and turnover frequencies (TOF) up to 7200 h−1
提出了一种使用均相铑催化通过分子氢作为还原剂对醛类进行还原胺化反应合成叔胺的方法。使用胺/醛比率为4/1时,可以由9种不同的醛和9种不同的仲胺合成叔胺,其选择性高达99%,周转频率(TOF)高达7200 h -1... 反应显示出对醇和酯功能的高耐受性,从而允许形成多功能分子。另外,仲胺也可以通过该合成来制备。对于所有化合物,活性都是通过吸收氢气来确定的。为了增加该过程的可持续性和效率,已经成功地制定了剂量策略。使用确定的反应指标,可以化学计量使用醛和胺,而不会显着降低选择性。
Reductive Amination of Aldehydes and Ketones with Sodium Triacetoxyborohydride. Studies on Direct and Indirect Reductive Amination Procedures<sup>1</sup>
作者:Ahmed F. Abdel-Magid、Kenneth G. Carson、Bruce D. Harris、Cynthia A. Maryanoff、Rekha D. Shah
DOI:10.1021/jo960057x
日期:1996.1.1
triacetoxyborohydride is presented as a general reducing agent for the reductiveamination of aldehydes and ketones. Procedures for using this mild and selective reagent have been developed for a wide variety of substrates. The scope of the reaction includes aliphatic acyclic and cyclic ketones, aliphatic and aromatic aldehydes, and primary and secondary amines including a variety of weakly basic and
the one-pot hydrogenation of the nitro group and the reductive alkylation of the amines. While aliphatic amines were effectively converted to the corresponding tertiary amines under Pd/C-catalyzed conditions, Rh/C was a highly effective catalyst for the N-monoalkylation of aliphatic primary amines without over-alkylation to the tertiary amines. Furthermore, the combination of the Rh/C-catalyzed N-monoalkylation
The TiCl4-catalyzed reaction of aromatic carbonyl compounds with (dialkylamino)dimethylsilanes gave tertiary amines in moderate to high yields. The reductive amination of aliphatic aldehydes was effectively catalyzed by ZnI2. Methyl N-(dimethylsilyl)carbamate as well could be used for reductive amination of carbonyl compounds in the presence of Ph3CClO4.
Controlled reduction of tertiary amides to the corresponding aldehydes or amines using dialkylboranes
作者:Gayane Godjoian、Bakthan Singaram
DOI:10.1016/s0040-4039(97)00179-2
日期:1997.3
tertiary amides were reduced using one or two equivalents of various dialkylboranes, such as 9-borabicyclo[3.3.1] nonane (9-BBN), dicyclohexylborane (Chx2BH), or disiamylborane (Sia2BH). The reduction of tertiary amides having alkyl substituents of varying steric requirement at the nitrogen atom, required two equivalents of 9-BBN for complete reduction and gave the corresponding tertiary amines. However