SYNTHESIS IN THE FIELD OF THE ERYTHRINA ALKALOIDS: PART I. THE SYNTHESIS OF HEXAHYDROAPOERYSOTRINE

1957 ◽  
Vol 35 (7) ◽  
pp. 651-662 ◽  
Author(s):  
B. Belleau
Keyword(s):  
Reaction Mechanisms ◽  
Polyphosphoric Acid ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Ring System ◽  
Ring Closure ◽  
Lithium Aluminum ◽  
Natural Origin ◽  
Erythrina Alkaloids ◽  
Acid Reduction

The synthesis of the complete ring system of the aromatic class of Erythrina alkaloids is described. The basic sequence involves reaction of hexahydroindole (whose preparation was studied in some detail) with phenylacetyl chloride to give the ketoamide (VII) which suffered ring closure to the desired ring system (XI) when treated with polyphosphoric acid. Reduction of XI with lithium aluminum hydride gave the corresponding base (XIII). Evidence in support of structure XI is presented. Application of the same sequence with homoveratroyl chloride as starting material led ultimately to the spiroamine (XIV) which proved identical with a sample of natural origin. The stereochemistry of the spiroamines is discussed and the reaction mechanisms involved are critically examined. The new cyclization reaction was successfully applied to the system phenylacetamide–cyclohexanone in an effort to explore its scope.

CLEAVAGE OF XANTHENE ETHERS: A NEW ROUTE TO 9-SUBSTITUTED XANTHENES

1964 ◽  
Vol 42 (7) ◽  
pp. 1736-1740 ◽  
Author(s):  
N. Latif ◽  
I. Fathy ◽  
N. Mishriky
Keyword(s):  
Reaction Mechanisms ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Active Hydrogen ◽  
Cyanoacetic Ester

9,9-(Tetrachloro-o-phenylenedioxy) xanthene (IIa) and its thio-analogue (IIb) are cleaved by hydrazines to give the corresponding hydrazones of xanthone and thiaxanthone, respectively, together with tetrachlorocatechol. The unsaturated nitriles (Va), (Vb), and (Vc) are produced similarly by the action of malononitrile and cyanoacetic ester. Dixanthenyl ether itself reacts in a similar manner with active hydrogen compounds to give the corresponding 9-xanthyl derivatives. (IIb) is prepared by the action of 9-diazothiaxanthene on tetrachloro-o-benzoquinone and is readily cleaved by lithium aluminum hydride to give thiaxanthene and tetrachlorocatechol. The reaction mechanisms are discussed.

SYNTHESIS IN THE SERIES OF ERYTHRINA ALKALOIDS: II. STERIC CONFIGURATION OF THE SYNTHETIC BASE

1950 ◽  
Vol 28b (11) ◽  
pp. 745-749 ◽  
Author(s):  
E. D. Clair ◽  
F. H. Clarke ◽  
W. A. Edmiston ◽  
K. Wiesner
Keyword(s):  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Acid Ethyl Ester ◽  
Ring Closure ◽  
Lithium Aluminum ◽  
Neutral Medium ◽  
Amino Ester ◽  
Trans Form ◽  
Hydride Reduction ◽  
Steric Configuration

2-Cyclohexanone acetic acid ethyl ester oxime was hydrogenated in acidic medium to the corresponding amino ester, which is of the cis form, as by ring closure it gives a hexahydroöxindole which in turn is reduced by lithium aluminum hydride to cis-octahydroindole. Also, it has been shown that the amino ester can be transformed into cis-aminoethylcyclohexane. The high pressure Raney nickel hydrogenation of the oxime ester followed by lithium aluminum hydride reduction gave also cis-octahydroindole, although in neutral medium the trans form could have been expected.

STUDIES IN THE WAGNER-MEERWEIN REARRANGEMENT. PART I

1956 ◽  
Vol 34 (7) ◽  
pp. 991-1005 ◽  
Author(s):  
F. A. L. Anet ◽  
P. M. G. Bavin
Keyword(s):  
Formic Acid ◽  
Polyphosphoric Acid ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Ester Group ◽  
Lithium Aluminum ◽  
Methyl Ethyl ◽  
Mild Conditions ◽  
Convenient Route ◽  
Simultaneous Loss

The preparation by a convenient route of 9-methyl, ethyl, isopropyl, l-butyl, and benzyl phenanthrenes is described. This consists of the alkylation of methyl fluorene-9-carboxylate under mild conditions, reduction of the ester group with lithium aluminum hydride, and then tosylation of the carbinol. The tosyl esters so prepared rearrange to alkylphenanthrenes with simultaneous loss of the elements of toluenesulphonic acid, when heated alone or in formic acid. Dehydration of the carbinols at 160 ° with polyphosphoric acid also promotes rearrangement.

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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