Some more Akabori Reaction papers, in Japanese, that badly require translation:
Studies on Reactions between Aromatic Aldehydes and a-Amino Acids: I New Facts on Akabori Reaction
Eiichi Takagi
Yakugaku Zasshi
Vol.71(7) 1951 pp.648-651
Abstract
As a result of studies on Akabori reaction (A formula), the following facts were found: (1) In the reaction between benzaldehyde and dl-N-methylalanine, dl-ephedrine and dl-f-ephedrine are obtained irrespective of the use of pyridine. (2) Similarly, two kinds of dl-compounds of 1-(3, 4-methylenedioxyphenyl)-2-methylaminopropane-1-ol are obtained by heating directly piperonal and dl-N-methylalanine. (3) A new reaction (B formula), differing from the Akabori reaction, takes place by heating directly benzaldehyde and dl-alanine by which benzylamine, 1, 2-diphenylethanolamine (2 kinds of dl-
compounds), acetaldehyde and carbon dioxide are formed. From above results, it has been assumed that, when the amino radical in the amino acids used is primary, the reaction of B-type occurs, while when it is secondary, the A-type reaction occurs.
Studies on Reactions between Aromatic Aldehydes and a-Amino Acids: II A New Reaction giving Alkamines and 1, 2-Diphenylethanolamine Series (Part 1)
Eiichi Takagi, Hiroshi Ichikawa and Isao Ensaka
Yakugaku Zasshi
Vol.71(7) 1951 pp.652-655
Abstract
It has been found that the new reaction that took place as a result of reacting benzaldehyde and dl-alanine was a common reaction among the allied aliphatic a-amino acids. The basic substances obtained by reacting benzaldehyde with dl-a-aminoisobutyric acid, dl-a-aminobutyric acid and glycine, respectively, were found to he benzylamine and two kinds of dl-compounds of 1, 2-
diphenylethanolamine. The carbonyl compounds obtained as their by-product, were found to be acetone and propionaldehyde in the first two cases, but the third was not the formaldehyde expected. From the considertions of the present and the previous experiments on dl-alanine, it seems that these reactions follow the general reaction as represented by equation (I).
Studies on Reactions between Aromatic Aldehydes and a-Amino Acids: III A New Reaction giving Alkamines and 1, 2-Diphenylethanolamine Series (Part 2)
Eiichi Takagi
Yakugaku Zasshi
Vol.71(7) 1951 pp.655-657
Abstract
The new reaction previously found was tested with (i) anisaldehyde and dl-alanine; (ii) piperonal and dl-alanine, and (iii) piperonal and dl-a-aminoisobutyric acid, and in these cases, also, the new reactions were found to take place. A reaction of aliphatic a-amino acids possessing a
tertiary amino group, such as dl-dimethylalanine and dl-a-dimethylaminoisobutyric acid, with benzaldehyde was tried but decarboxylation failed to take place in these cases. It has been known that the reaction of benzaldehyde and dl-alanine in the presence of pyridine yields dl-?-norephedrine but, in this case too, the new reaction was found to have taken place. Summarizing the results obtained in the past three reports, it can be said that the reaction between aromatic aldehydes and aliphatic a-amino acids proceed in three different ways according to the kind of the amino group present: (i) The new reaction occurs with primary amino group; (ii) Akabori reaction chiefly takes place with secondary amino group; and (iii) no reaction occurs in the case of tertiary amino group.
Studies on Reactions between Aromatic Aldehydes and a-Amino Acids: IV (Untitled)
Eiichi Takagi
Yakugaku Zasshi
Vol.71(7) 1951 pp.657-
662
Abstract
In connection with the reaction of aromatic aldehydes and a-amino acids, Akabori reactions of optically active amino acids were examined in the case of benzaldehyde and l(+)-N-methylalanine, and it was found that no optically active product could be obtained. As a general summarization of the experimental results obtained to date, the differences in reactions due to primary, secondary and tertiary amino groups were considered from the reaction mechanism and explanations reached through the electronic theory. In addition, from a qualitative observations on the reactions between aromatic aldehydes and a-amino acids, the following were found to be true: (i) The acyl derivatives of a-amino acids do not react; (ii) compounds such as anthranilic acid in which the amino group is directly attached to the aromatic nucleus also fail to react; and (iii) special kinds of carbonyl compounds, such as enanthaldehyde, cinnamaldehyde and benzoin, also react as
aldehydes.
On the New Reaction Giving Alcamines of Ephedrine and Adrenaline Series*
Shiro Akabori and Kakitu Momotani
Nippon Kagaku Kaishi
Vol.64(5) 1943 pp.608-611
DOI:10.1246/nikkashi1921.64.608
Abstract
In Japanese
* The oft cited and equally often considered imaginary 1943 article by Akabori & Momotani
107. Über eine neue Bildungsweise des Ephedrins und der verwandten Verbindungen. Zur Biogenese von Ephedrin und Adrenalin*
Shiro Akabori and Kakitu Momotani
Proc. Imp. Acad (Jap)
Vol.17(10) 1941 pp.506-509
DOI:10.2183/pjab1912.17.506
Abstract
Ephedrin wurde zuerst von Prof. Nagai im Jahre 1884 aus der chinesischen Droge Ma Huang (Ephedra vulgaris var.) in reinem
Zustand isoliert. Die chemische Konstitution des Ephedrins ist durch die Untersuchungen von Nagai, Kanao, Ladenburg, Schmidt, Spath und Emde auf analytischem sowie auf sunthetischen Wege als 1-Phenyl-1-oxy-2-methylamino-propan festgetellt worden.
* This paper is unusual in this series, there is a translation issue - but not Japanese to English, rather it is in German and gives pretty clear procedural details from what I can see.
Reaction of Free Amino Acids with Aldehydes; One-Step Synthesis of Amino Alcohol (Akabori Reaction)*
Yuusaku Yokoyama,* Natsume Tsubaki, Tomotsugu Yamaguchi, Hiroaki Okuno
Abstract
We established the one-pot synthesis of ephedrine by the reaction of N-methylalanine with benzaldehyde by improvement of the reported reaction by Akabori in 1942. The formation of unstable oxazolidine was newly detected based on NMR analysis. After
the reaction, the mixture was directly heated with aqueous AcOH to give ephedrine in 48% yield. The reaction of benzaldehyde having electron donating group on benzene ring gave excellent yield (87%). This reaction is a new type of the reaction of amino acid that is involved a decarboxylative C-C forming reaction on the asymmetric carbon atom.
*NB Apparently unpublished - this is from a Conference/proceedings from memory. Thus it is kind of imperative that some more details come to light regarding this procedure.
These are crying out to be understood - with these the paper that was found online, could potentially be understood and maybe even applied.
The synthesis of N-substituted ureas I - The N-alkylation of ureas.pdf
: 1269-1271