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 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.

Reaction of Lithium Aluminum Hydride with Compounds Containing Active Hydrogen

1948 ◽  
Vol 70 (2) ◽  
pp. 486-489 ◽  
Author(s):  
J. A. Krynitsky ◽  
J. E. Johnson ◽  
H. W. Carhart
Keyword(s):  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Active Hydrogen

Micro determination of active hydrogen in organic compounds by lithium-aluminum hydride

1954 ◽  
Vol 42 (1) ◽  
pp. 81-84 ◽  
Author(s):  
D. Subba Kao ◽  
G. D. Shah ◽  
V. S. Pansare
Keyword(s):  
Organic Compounds ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Active Hydrogen

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.

Sign in / Sign up

Export Citation Format

Share Document