Stereospecific reactions of cis- and trans-3-Aminochroman-4-ols

1977 ◽  
Vol 30 (10) ◽  
pp. 2205 ◽  
Author(s):  
BV Lap ◽  
LR Williams
Keyword(s):  
Amino Alcohol ◽  
Nitrous Acid ◽  
Potassium Hydroxide ◽  
Amino Alcohols ◽  
Ring Closure ◽  
Stereospecific Reactions ◽  
Cyclic Amide ◽  
Cis And Trans ◽  
Effect Ring ◽  
Chemical Evidence

Stereospecific reactions of epimeric 3-amino-6-methylchroman-4-ols (1 and 2; R = Me) have provided chemical evidence for their configuration and have led us to reverse the configurations that we had assigned previously to the 6-bromo analogues on the basis of N.M.R. data. ��� The 2-chloro-N-(4-hydroxy-6-methylchroman-3-yl)acetamides (3) and (4) were treated with potassium hydroxide in ethanol in an attempt to effect ring closure. The cis-chloroacetamide (4) gave a cyclic amide (5) while the trans-chloroacetamide (3) reacted with solvent to form the trans-3-ethoxyacetamidochroman-4-ol (6). ��� The configurations of the amino alcohols were confirmed by a study of their reactions with nitrous acid where deamination of the cis-amino alcohol gave the chroman-4-one (9) while the trans-amino alcohol gave a trans-diol (10) by an epoxide intermediate.

ChemInform Abstract: Synthesis of 1,2- and 1,4-Amino Alcohols from 1,3-Dienes via Oxazines. Rearrangements of 1,4-Amino Alcohol Derivatives to Oxazolines.

ChemInform ◽  
2010 ◽  
Vol 41 (37) ◽  
pp. no-no
Author(s):  
Lukas Werner ◽  
Jason Reed Hudlicky ◽  
Martina Wernerova ◽  
Tomas Hudlicky
Keyword(s):  
Amino Alcohol ◽  
Amino Alcohols

Stereochemical studies. Part 31. Ring closure reaction of cis- and trans-2-(bromomethyl)cycloalkylamines

1979 ◽  
pp. 1770-1773 ◽  
Author(s):  
György Göndös ◽  
Kornélia L. Láng ◽  
Andrea Szeghy ◽  
György Dombi ◽  
Gábor Bernáth
Keyword(s):  
Ring Closure ◽  
Cis And Trans

Tricyclic psychotropic agents containing two chalcogen atoms in the central ring: 8-Substituted 6-(4-piperidyl)-6H-dibenz[b,e]-1,4-oxathiepins

1982 ◽  
Vol 47 (11) ◽  
pp. 3077-3093 ◽  
Author(s):  
Karel Šindelář ◽  
Jiřina Metyšová ◽  
Jiří Holubek ◽  
Emil Svátek ◽  
Jiří Protiva ◽  
...  
Keyword(s):  
Secondary Amine ◽  
Amino Alcohol ◽  
Sodium Hydride ◽  
Amino Alcohols ◽  
Central Ring ◽  
Psychotropic Agents ◽  
High Degree ◽  
By Products ◽  
Antiapomorphine Effect ◽  
Central Depressant

2-(2-Fluorophenylthio)benzaldehydes IXa-c and 5-chloro-2-(2-fluorophenylthio)acetophenone were treated with 1-methyl-4-piperidylmagnesium chloride and 3-dimethylaminopropylmagnesium chloride, respectively, and the resulting amino alcohols VIa-c, XVII and XVIII were cyclized with sodium hydride in dimethylformamide. In addition to the title compounds Ia-c, XIX and XX, several types of by-products were obtained. Demethylation of compound Ib by the chloroformate method afforded the secondary amine IIb which was transformed to the amino alcohols IIIb and Vb. Compounds Ia-c are very potent neuroleptics with a high degree of central depressant and cataleptic activity. The amino alcohol Vb exhibits a very strong antiapomorphine effect in rats.

scholarly journals Regioselective and Stereodivergent Synthesis of Enantiomerically Pure Vic-Diamines from Chiral β-Amino Alcohols with 2-Pyridyl and 6-(2,2′-Bipyridyl) Moieties

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 727 ◽  
Author(s):  
Marzena Wosińska-Hrydczuk ◽  
Przemysław J. Boratyński ◽  
Jacek Skarżewski
Keyword(s):  
Ring Opening ◽  
Amino Alcohols ◽  
Ring Closure ◽  
Mitsunobu Reaction ◽  
Hydroxyl Group ◽  
Hydrazoic Acid ◽  
Enantiomerically Pure ◽  
Endocyclic Nitrogen Atom ◽  
Diastereomeric Mixture ◽  
Complete Series

In this report, we describe the synthetic elaboration of the easily available enantiomerically pure β-amino alcohols. Attempted direct substitution of the hydroxyl group by azido-functionality in the Mitsunobu reaction with hydrazoic acid was inefficient or led to a diastereomeric mixture. These outcomes resulted from the participation of aziridines. Intentionally performed internal Mitsunobu reaction of β-amino alcohols gave eight chiral aziridines in 45–82% yield. The structural and configuration identity of products was confirmed by NMR data compared to the DFT calculated GIAO values. For 1,2,3-trisubstituted aziridines slow configurational inversion at the endocyclic nitrogen atom was observed by NMR at room temperature. Moreover, when aziridine was titrated with Zn(OAc)2 under NMR control, only one of two N-epimers directly participated in complexation. The aziridines underwent ring opening with HN3 to form the corresponding azido amines as single regio- and diastereomers in 90–97% yield. Different results were obtained for 1,2-disubstituted and 1,2,3-trisubstituted aziridines. For the later aziridines ring closure and ring opening occurred at different carbon stereocenters, thus yielding products with two inverted configurations, compared to the starting amino alcohol. The 1,2-disubstituted aziridines produced azido amines of the same configuration as the starting β-amino alcohols. To obtain a complete series of diastereomeric vic-diamines, we converted the amino alcohols into cyclic sulfamidates, which reacted with sodium azide in SN2 reaction (25–58% overall yield). The azides obtained either way underwent the Staudinger reduction, giving a series of six new chiral vic-diamines of defined stereochemistries.

scholarly journals Continuous and convergent access to vicinyl amino alcohols

2015 ◽  
Vol 51 (82) ◽  
pp. 15133-15136 ◽  
Author(s):  
Tomoya Nobuta ◽  
Guozhi Xiao ◽  
Diego Ghislieri ◽  
Kerry Gilmore ◽  
Peter H. Seeberger
Keyword(s):  
Amino Alcohol ◽  
Amino Alcohols ◽  
Assembly System

A four module convergent chemical assembly system delivers two classes of vicinyl amino alcohol and five APIs.

Synthesis of 1,2-amino alcohols via catalytic C–H amidation of sp3 methyl C–H bonds

2014 ◽  
Vol 50 (81) ◽  
pp. 12073-12075 ◽  
Author(s):  
Taek Kang ◽  
Heejeong Kim ◽  
Jeung Gon Kim ◽  
Sukbok Chang
Keyword(s):  
Amino Alcohol ◽  
Amino Alcohols ◽  
Chelating Groups

A new route to 1,2-amino alcohols is presented by C–H amidation of sp3 methyl C–H bonds as a key step. Various alcohols were employed after converting them to removable ketoxime chelating groups. Iridium-catalyzed C–H amidation and following LAH reduction furnished β-amino alcohol products.

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