One-Pot Synthesis of Fatty Amines: Rh-Catalyzed Hydroaminomethylation of 1-Decene in an Aqueous Microemulsion System—Influence of Reaction Conditions on the Reaction Performance

Abstract

The hydroaminomethylation of the long-chain olefin 1-decene and diethylamine with a homogeneous Rh(acac)(cod)/SulfoXantphos catalyst complex as a one-pot synthesis was investigated. The influence of reaction conditions such as temperature and synthesis gas pressure was determined, as well as the effects of the initial concentrations of catalyst precursor, ligand, and reactants on the yield of fatty amine. Hydroaminomethylation was successfully carried out in an aqueous microemulsion system using a non-ionic surfactant with a reaction time of 2 h. A maximum yield of 34%, high regioselectivities >97%, and chemoselectivities >85% were achieved.

Continuous Homogeneously Catalyzed Production of Fatty Amines in Microemulsions─Proof of Concept in a Mini-Plant

“…HAM is one such tandem reaction in which aldehydes are produced from alkenes (Hyfo) and then directly converted to amines (RA). To fully understand the complex HAM, the underlying reaction steps of Hyfo and RA have to be investigated separately. , The Hyfo of dodecene in MES ,,,, has already been researched in depth and was successfully operated in a continuous mini-plant in our group. , Since then, the RA of undecanal and HAM of decene in MES have also been investigated at a laboratory scale. The aim of the current investigation is to build on the knowledge from the lab investigation and extend it to a scaled-up continuous operation where otherwise inaccessible information about long-term catalyst stability and side product accumulation can be gained.…”

“…31,32 The Hyfo of dodecene in MES 15,25,31,33,34 has already been researched in depth and was successfully operated in a continuous mini-plant in our group. 17,35 Since then, the RA of undecanal 36 and HAM of decene 37 in MES have also been investigated at a laboratory scale. The aim of the current investigation is to build on the knowledge from the lab investigation 36 and extend it to a scaled-up continuous operation where otherwise inaccessible information about long-term catalyst stability and side product accumulation can be gained.…”

2‐Arylpropylamines from 1‐Propenylbenzenes in a New One‐Pot Metathesis–Hydroaminomethylation Protocol

“…Rh-catalyzed HAM has been recently used for the synthesis of indoles or indoline-2-ols, [13] gamma-aminobutyric esters, [14] beta-aminoesters [15] in homogeneous catalysis. Also, in several recent studies the catalyst was supported on an immiscible liquid phase [16][17][18][19] or on polymers [20,21] to facilitate the recycling. The use of an additional catalyst for the reductive amination step allowed for a drastic reduction on the temperature and syngas pressure.…”

Hydroaminomethylation of Natural Allylic and Homoallylic Alcohols: A Ligand‐Controlled Route to New Amines

“…Due to the further development of more efficient cobalt and rhodium catalysts and the introduction of phosphorus ligands, HAM has become a powerful method for the synthesis of amines. [4][5][6][7][8][9][10][11][12][13][14][15] As HAM is a tandem catalytic process in which various catalytic cycles occur simultaneously, the conditions can be good for one catalytic cycle and deleterious for the other. For this reason, care in the choice of appropriate conditions is critical for the successful reaction sequence.…”

“…However, selectivity for amines was low and the reaction required harsh conditions (T>300 °C and pressures up to 150 bar). Due to the further development of more efficient cobalt and rhodium catalysts and the introduction of phosphorus ligands, HAM has become a powerful method for the synthesis of amines [4–15] . As HAM is a tandem catalytic process in which various catalytic cycles occur simultaneously, the conditions can be good for one catalytic cycle and deleterious for the other.…”