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

scholarly journals A Facile Synthesis of 3-(Chloromethyl)-2-methyl-1,1′-biphenyl

2019 ◽  
Vol 31 (12) ◽  
pp. 3009-3011
Author(s):  
Lele Zhang ◽  
Songbo Cheng ◽  
Hang Hu ◽  
Defeng Xu
Keyword(s):  
High Risk ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
High Yield ◽  
Synthesis Process ◽  
Lithium Aluminum ◽  
Efficient Synthesis ◽  
Facile Synthesis ◽  
Synthetic Process ◽  
Safety Issues

3-(Chloromethyl)-2-methyl-1,1′-biphenyl is a key intermediate for the preparation of bifenthrin, an insecticide which belongs to pyrethroid. The traditional synthetic process of 3-(chloromethyl)-2-methyl- 1,1′-biphenyl is complicated and involves high-toxic and high-risk reagents such as thionyl chloride, lithium aluminum hydride and methyl iodide, which causes significant environmental problems and safety issues. Herein, a facile and efficient synthesis process of 3-(chloromethyl)-2- methyl-1,1′-biphenyl was developed. The synthetic process is shortened from 6 steps to only 4 steps and avoids the use of high-toxic and high-risk reagents. Moreover, 3-(chloromethyl)-2-methyl-1,1′-biphenyl can be obtained by simple purification process in high yield (73.9 %). Compared with the traditional synthetic process, the synthetic process of 3-(chloromethyl)-2-methyl-1,1′-biphenyl reported here is more environmental friendly and efficient.

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).

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.

The Preparation of Specifically Deuterated trans- Cinnamyl Alcohol and trans- Cinnamic Acid

1973 ◽  
Vol 51 (13) ◽  
pp. 2102-2104 ◽  
Author(s):  
Donald G. Lee ◽  
James R. Brownridge
Keyword(s):  
Cinnamic Acid ◽  
Triple Bond ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Cinnamyl Alcohol ◽  
Partial Reduction ◽  
Work Up

The reduction of ethyl phenylpropiolate by lithium aluminum hydride results in partial reduction of the triple bond to give trans-cinnamyl alcohol. If ethyl phenylpropiolate is reduced by LiAlD4 followed by work-up with acetone and H2O the product is the specifically labeled compound, trans-3-phenyl-2-propen-1-ol-1,1,2-d3. If the ester is reduced with LiAlH4 followed by work-up with acetone-d6 and D2O the product is trans-3-phenyl-2-propen-1-ol-O,3-d2. Oxidation of these two products by sodium ruthenate leads to formation of trans-cinnamic acid-α-d and trans-cinnamic acid-β-d, respectively.

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