A total synthesis of (±)-triophamine

1984 ◽  
Vol 62 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Edward Piers ◽  
J. Michael Chong ◽  
Kirk Gustafson ◽  
Raymond J. Andersen
Keyword(s):  
Total Synthesis ◽  
Sulfur Trioxide ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Yield Reduction ◽  
Diisobutylaluminum Hydride ◽  
H Nmr ◽  
Isomeric Acid ◽  
Nitrophenyl Ester

Treatment of ethyl 2-pentynoate (14) with lithium (phenylthio)(tri-n-butylstannyl)cuprate (12) afforded, in 76% yield, ethyl (Z)-3-(tri-n-butylstannyl)-2-pentenoate (15). On the other hand, when compound 14 was allowed to react with the (tri-n-butylstannyl)copper reagent 13, ethyl (E)-3-(tri-n-butylstannyl)-2-pentenoate (21) was produced in 83% yield. Reduction (diisobutylaluminum hydride, ether) of the esters 15 and 21 gave the alcohols 16 and 22, respectively. Treatment of each of the latter substances with pyridine – sulfur trioxide complex, followed by further reduction of the resultant intermediates with lithium aluminum hydride, provided the geometrically isomeric alkenylstannanes 17 and 23. Conjugate addition of (E)-3-lithio-2-pentene (18) (formed by transmetalation of 17) to compound 19 produced the olefinic trimethylhydrazide 20, which was converted (diisobutylaluminum hydride, ether; pyridinium dichromate, dimethylformamide) into the corresponding carboxylic acid 2. Subjection of compound 23 to a sequence of reactions identical with that used for the conversion of 17 into 2 provided the isomeric acid 3, which was identical (infrared, 1H nmr) with the natural acid derived from triophamine (1). Conversion of 3 into the p-nitrophenyl ester 26, followed by condensation of the latter substance with guanidine, afforded a chromatographically separable mixture of (±)-triophamine (1) and the corresponding diastereomer.

Synthesis of β-amino-α-ferrocenyl alcohols

2005 ◽  
Vol 2005 (11) ◽  
pp. 712-715 ◽  
Author(s):  
Hai-Ying Zhao ◽  
Zhan-Xi Bian ◽  
Bao-Guo Li
Keyword(s):  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Chain Structure ◽  
Lithium Aluminum ◽  
Polymeric Chain ◽  
X Ray ◽  
H Nmr ◽  
Hydrogen Bonding Interactions ◽  
Trimethylsilyl Ethers ◽  
New Compounds

β-Amino-α-ferrocenyl alcohols [FcC(OH)(R)CH2NH2] (R = Me, Et, nPr, iPr, Ph, p-MeOC6H4, o-ClC6H4, m-ClC6H4, p-ClC6H4, Fc; Fc = C5H4FeC5H5) were prepared by the reduction of cyanohydrin trimethylsilyl ethers of acylferrocenes with lithium aluminum hydride. All new compounds were characterised by elemental analysis, IR and 1H NMR spectroscopies. The X-ray crystal structure of β-amino-α,α-diferrocenylethanol shows that it has a polymeric chain structure with hydrogen bonding interactions between the OH proton and the N of NH2.

Total Synthesis of Several Monodeoxy and Dideoxy-DL-hexopyranoses from 6,8-Dioxabicyclo[3.2.1]oct-2-ene and 6,8-Dioxabicyclo[3.2.1]oct-3-ene

1971 ◽  
Vol 49 (12) ◽  
pp. 2132-2138 ◽  
Author(s):  
T. P. Murray ◽  
U. P. Singh ◽  
R. K. Brown
Keyword(s):  
Hydrochloric Acid ◽  
Total Synthesis ◽  
Dilute Hydrochloric Acid ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Osmic Acid ◽  
Aqueous Base

Reaction of osmic acid with 6,8-dioxabicyclo[3.2.1]oct-3-ene (1) gave 1,6-anhydro-4-deoxy-β-DL-ribo-hexopyranose (3, R = H) which was hydrolyzed to 4-deoxy-α,β-DL-ribo-hexopyranose (4, R = H). Conversion of 1 to 1,6:2,3-dianhydro-4-deoxy-β-DL-ribo-hexopyranose (5) followed by treatment of 5 with lithium aluminum hydride, gave 1,6-anhydro-3,4-dideoxy-β-DL-erythro-hexopyranose (6, R = H), and this in turn was hydrolyzed to 3,4-dideoxy-α,β-DL-erythro-hexopyranose (7, R = H).Reaction of osmic acid with 6,8-dioxabicyclo[3.2.1]oct-2-ene (2) gave 1,6-anhydro-2-deoxy-β-DL-riob-hexopyranose (8, R = H), which was hydrolyzed to 2-deoxy-DL-riob-hexopyranose (9, R = H). Compound 2 was converted to 1,6:3,4-dianhydro-2-deoxy-β-DL-ribo-hexopyranose (10) which was hydrolyzed by aqueous base to 1,6-anhydro-2-deoxy-β-DL-arabino-hexopyranose (12) and this in turn was hydrolyzed by dilute hydrochloric acid to 2-deoxy-α,β-DL-arabino-hexopyranose (2-deoxy-DL-glucose) (13). The reaction of 10 with lithium aluminum hydride gave 1,6-anhydro-2,3-dideoxy-β-DL-erythro-hexopy-ranose (14).Yields were good to excellent in each of the above reactions.

Determination of the absolute stereochemistry of the fungal metabolite (R)-(−)-2-(4′-hydroxyphenyl)-2-hydroxyethanoic acid (pisolithin B)

1991 ◽  
Vol 69 (5) ◽  
pp. 772-778 ◽  
Author(s):  
Youla S. Tsantrizos ◽  
Kelvin K. Ogilvie
Keyword(s):  
Absolute Configuration ◽  
Lithium Aluminum Hydride ◽  
Optical Rotation ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Fungal Metabolite ◽  
H Nmr ◽  
The Absolute ◽  
Absolute Stereochemistry

The antifungal antibiotic pisolithin B (p-hydroxymandelic acid, 2-(4′-hydroxyphenyl)-2-hydroxyethanoic acid, 1a) was shown to have the absolute (R) configuration. The stereochemistry was established via comparison of its optical rotation to that of its synthetic (R) and (S) enantiomers. The synthetic samples were prepared by the stereospecific reduction of the prochiral α-keto acid, p-hydroxybenzoylformic acid (2-(4′-hydroxyphenyl)-2-oxoethanoic acid, 2a), with (R) or (S)-2,2′-dihydroxy-1,1′-binaphthyl lithium aluminum hydride (BINAL-H). The absolute configuration and enantiomeric purity of both products were determined using the 1H NMR of their isobutyl esters in the presence of the chiral solvating agent (R)-(−)-2,2,2-trifluoro-1-(9-anthryl)ethanol. Key words: pisolithin B, p-hydroxymandelic acid, antifungal, absolute configuration.

Total Synthesis of DL-Glucose, 3-O-Methyl-DL-glucose, and 3-Deoxy-DL-ribo-hexopyranose from 1,6:3,4-Dianhydro-β-DL-allo-hexopyranose, a Product Obtained from Acrolein Dimer

1971 ◽  
Vol 49 (20) ◽  
pp. 3342-3347 ◽  
Author(s):  
U. P. Singh ◽  
R. K. Brown
Keyword(s):  
Total Synthesis ◽  
Acid Hydrolysis ◽  
Sodium Methoxide ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Barium Hydroxide ◽  
Lithium Aluminum ◽  
Methyl Glycoside ◽  
Acid Catalyzed ◽  
Hydrolysis Of

The reaction of butyllithium in ether with 1,6:2,3-dianhydro-4-deoxy-β-DL-ribo-hexopyranose (1), a substance obtained in five steps from acrolein dimer, gave 1,6-anhydro-3,4-dideoxy-β-DL-erythro-hex-3-enopyranose (2). The compound 1,6:3,4-dianhydro-β-DL-allo-hexopyranose (3), obtained from 2, was converted by reaction with aqueous barium hydroxide followed by hydrolysis of the product, to DL-glucose 5. Treatment of 3 with sodium methoxide in methanol followed by acid hydrolysis of the 1,6-anhydro intermediate 6, gave 3-O-methyl-DL-glucose (7). The same intermediate, 6, along with the methyl glycoside 8, could be obtained by the acid-catalyzed reaction of 3 with methanol. Lithium aluminum hydride reacted with 3 to form 1,6-anhydro-3-deoxy-β-DL-ribo-hexopyranose (9), which was hydrolyzed readily to 3-deoxy-DL-ribo-hexopyranose (10).Yields were excellent throughout. All products obtained from the oxirane 3 were those resulting only from trans diaxial opening of the oxirane ring.

Notes: 7-Phenyl-2:6:8-trioxaspiro(3,5)-nonane: A High Yield Reduction with Lithium Aluminum Hydride

1959 ◽  
Vol 24 (11) ◽  
pp. 1832-1833 ◽  
Author(s):  
Riyad Nassar ◽  
Costas Issidorides
Keyword(s):  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
High Yield ◽  
Lithium Aluminum ◽  
Yield Reduction

Stereoselective Total Synthesis of Copa and Ylango Sesquiterpenoids: (+)-Copacamphor, (+)-Copaborneol, (+)-Copaisoborneol, (−)-Ylangocamphor, (−)-Ylangoborneol, (−)-Ylangoisoborneol

1975 ◽  
Vol 53 (19) ◽  
pp. 2838-2848 ◽  
Author(s):  
Edward Piers ◽  
Ronald W. Britton ◽  
M. Bert Geraghty ◽  
Robert J. Keziere ◽  
Fusao Kido
Keyword(s):  
Total Synthesis ◽  
Liquid Ammonia ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
High Yield ◽  
Lithium Aluminum ◽  
Alkylation Product ◽  
Intramolecular Alkylation ◽  
Enolate Anion ◽  
Stereoselective Syntheses

Efficient, stereoselective syntheses of the tricyclic sesquiterpenoids (+)-copacamphor (3), (+)-copaborneol (4), (+)-copaisoborneol (5), (−)-ylangocamphor (6), (−)-ylangoborneol (7), and (−)-ylangoisoborneol (8) are described. Conversion of the keto acetate 9 (previously synthesized from the dione 1) into the keto tosylate 17 was accomplished via an eight-step sequence. Intramolecular alkylation of 17 afforded, in high yield, (+)-copacamphor (3), which had previously been converted into the corresponding alcohols 4 and 5 by Kolbe-Haugwitz and Westfelt. Alkylation of the enolate anion of the bicyclic dione 2 with 2-bromopropane in hexamethylphosphoramide gave mainly the O-alkylation product 19. Conversion of 19 into the keto mesylate 29 was carried out in 5 synthetic steps. Intramolecular alkylation of 29 afforded (−)-ylangocamphor (6). Reduction of the latter with calcium in liquid ammonia gave (−)-ylangoborneol (7), while reduction with lithium aluminum hydride yielded (−)-ylangoisoborneol (8).

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