Hydrolysis of the aluminum hydride complex of permethylcylopentadienyltitanocene with C-H bond activation

1986 ◽  
Vol 35 (4) ◽  
pp. 874-875
Author(s):  
�. B. Lobkovskii ◽  
A. I. Sizov ◽  
B. M. Bulychev ◽  
G. L. Soloveichik ◽  
I. V. Sokolova
Keyword(s):  
Bond Activation ◽  
Aluminum Hydride ◽  
Hydride Complex ◽  
Hydrolysis Of

PSEUDACONITINE, AND THE STEREOCHEMICAL RELATIONSHIP OF THE HIGHLY OXYGENATED ACONITE ALKALOIDS

1963 ◽  
Vol 41 (6) ◽  
pp. 1485-1489 ◽  
Author(s):  
Y. Tsuda ◽  
Léo Marion
Keyword(s):  
Acetic Acid ◽  
Absolute Configuration ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Reduction Product ◽  
Lithium Aluminum ◽  
Partial Hydrolysis ◽  
Previous Knowledge ◽  
Relationship Of ◽  
Hydrolysis Of

An alkaloid isolated from Aconitum spicatum Stapf has been found to be identical not only with the originally described pseudaconitine but also with 'α-pseudaconitine'. The product of the partial hydrolysis of the base, i.e., veratroylpseudaconine, is dextrorotatory, and not laevorotatory as recorded in the old literature. On heating, pseudaconitine undergoes pyrolysis, loses the elements of acetic acid, and gives rise to pyropseudaconitine. This substance, on treatment with lithium aluminum hydride, is converted to demethoxyisopyropseudaconine which is identical with the Wolff–Kishner reduction product of pyraconine. This correlation establishes that pseudaconitine and aconitine possess the same absolute configuration, which, in the light of previous knowledge, is extended also to indaconitine, delphinine, mesaconitine, and jesaconitine.

Arene C–H bond activation and methane formation by a methylplatinum(ii) complex: experimental and theoretical elucidation of the mechanism

2019 ◽  
Vol 43 (21) ◽  
pp. 8005-8014 ◽  
Author(s):  
Asma Nahaei ◽  
S. Masoud Nabavizadeh ◽  
Fatemeh Niroomand Hosseini ◽  
S. Jafar Hoseini ◽  
Mahdi M. Abu-Omar
Keyword(s):  
Bond Activation ◽  
Oxidative Addition ◽  
Methane Formation ◽  
Donor Atom ◽  
Computational Investigation ◽  
Hydride Complex

A combined experimental/computational investigation reveals that the cyclometalation of [PtMe2(DMSO)2], 1, by HC^N ligands proceeds via HC^N coordination through the N donor atom, oxidative addition of the arene C–H bond, and final dissociation of methane from a platinum hydride complex.

BIOCHEMISTRY OF THE USTILAGINALES: VIII. THE STRUCTURES AND CONFIGURATIONS OF THE USTILIC ACIDS

1953 ◽  
Vol 31 (4) ◽  
pp. 396-417 ◽  
Author(s):  
R. U. Lemieux
Keyword(s):  
Methyl Esters ◽  
Active Form ◽  
Aluminum Hydride ◽  
Optically Active ◽  
Lithium Aluminum ◽  
Acid Oxidation ◽  
Chromic Acid Oxidation ◽  
Pure Compounds ◽  
Hydrolysis Of ◽  
Derivatives Of

Methanolysis of ustilagic acid and hydrolysis of the methyl esters formed yielded a crystalline acidic fraction which was essentially a mixture of two substances termed the ustilic acids A and B. The acids were separated as their iso-propylidene derivatives. The ustilic acids cocrystallize to mixtures with melting points intermediate between those of the pure compounds. Conversion of ustilic acid A, m.p. 112–113 °C, [α]D −8° in methanol, which made up about 70% of the mixture, by hydrogenolysis to palmitic acid, by oxidation with chromic oxide to pentadecanedioic acid, and by lead tetraacetate oxidation followed by hydrogenation to 15-hydroxypentadecanoic acid showed the substance to be an optically active form of 15,16-dihydroxyhexadecanoic acid. Conversion of ustilic acid B, m.p. 140–141 °C, [α]D−10° in methanol, by sodium bismuthate oxidation followed by hydrogenation to 1,14-dihydroxytetradecane, by chromic acid oxidation of its methyl ester followed by hydrolysis of the product, and peroxide oxidation of the α-keto acid thus formed to tetradecanedioic acid, and by hydrogenolysis of the C2-carbon atom through a series of reactions to ustilic acid A, showed the substance to be an optically active form of 2,15,16-trihydroxy-hexadecanoic acid. Optically active forms of 2,15-dihydroxypentadecanoic and 2-hydroxypentadecanoic acids were prepared from ustilic acid B. Application of certain empirical rules of rotation to derivatives of these 2-hydroxyacids showed them to possess the D-configuration. Reduction of ustilic acid B with lithium aluminum hydride gave meso-1,2,15,16-tetrahydroxyhexadecane. Thus, ustilic acid B was the 2D,15D,16-trihydroxyhexadecanoic acid and the ustilic acid A was the 15D,16-dihydroxyhexadecanoic acid. Several derivatives of the above described acids were prepared.

DERIVATIVES OF DEHYDROABIETIC AND PODOCARPIC ACIDS

1963 ◽  
Vol 41 (8) ◽  
pp. 1924-1936 ◽  
Author(s):  
Ernest Wenkert ◽  
Peter Beak ◽  
Richard W. J. Carney ◽  
James W. Chamberlin ◽  
David B. R. Johnston ◽  
...  
Keyword(s):  
Methyl Esters ◽  
Resin Acid ◽  
Aluminum Hydride ◽  
Resin Acids ◽  
Lithium Aluminum ◽  
Hydride Reduction ◽  
Rate Of Hydrolysis ◽  
Keto Derivative ◽  
Hydrolysis Of ◽  
Derivatives Of

The lithium aluminum hydride reduction of nitriles in the aromatic resin acid series to aldimines and the conversion of the products to other derivatives are described. The effect of the stereochemistry of the nitriles on the rate of reduction is noted. The transformation of dehydroabietane into a dehydro product is indicated. The syntheses of a desoxydecarboxy-5,6-dehydro-7-keto derivative of podocarpic acid and its optical antipode are discussed. The stereochemistry of hydrogenation of 5,6-dehydro derivatives of podocarpic acid is reported. The effect of a 7-keto group on the rate of hydrolysis of methyl esters of aromatic resin acids is illustrated. The reactions of 6-bromo-7-keto derivatives of methyl podocarpate with bases are portrayed.

A simple synthesis of (±)-1,2,3,6-tetrahydro-2,3′-bipyridine (anatabine) and (±)-3-(2-piperidinyl)pyridine (anabasine) from lithium aluminum hydride and pyridine

1997 ◽  
Vol 75 (6) ◽  
pp. 616-620 ◽  
Author(s):  
Chi-Ming Yang ◽  
Dennis D. Tanner
Keyword(s):  
Catalytic Hydrogenation ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Simple Synthesis ◽  
Lithium Aluminum ◽  
Pyridine Solution ◽  
Hydrolysis Of

The hydrolysis of a pyridine solution of lithium tetrakis(N-dihydropyridyl)aluminate (LDPA), which was prepared at 0 °C, yields a mixture of 1,4-, 1,2-, and 2,5-dihydropyridines (DHPs) in a ratio of 26:37:38. The subsequent reversible base-catalyzed condensation of a 1:1 mixture of 1,2- and 2,5-DHPs carried out in the presence of oxygen affords an 89% yield of (±)-anatabine. When the reaction mixture is allowed to stand in the presence of oxygen, anabasine is slowly formed from anatabine by the reaction of the residual DHPs. Anatabine can also be converted into (±)-anabasine by catalytic hydrogenation. Keywords: lithium aluminum hydride, pyridine, anatabine, anabasine.

Synthesis of Enantiomeric N-(2-Phosphonomethoxypropyl) Derivatives of Purine and Pyrimidine Bases. I. The Stepwise Approach

1995 ◽  
Vol 60 (7) ◽  
pp. 1196-1212 ◽  
Author(s):  
Antonín Holý ◽  
Milena Masojídková
Keyword(s):  
Acid Hydrolysis ◽  
High Activity ◽  
Aluminum Hydride ◽  
Heterocyclic Base ◽  
Stepwise Approach ◽  
Pyrimidine Bases ◽  
Hydrolysis Of ◽  
Derivatives Of ◽  
Very High

The (R)- and (S)-N-(2-phosphonomethoxypropyl) derivatives of purine and pyrimidine bases (PMP derivatives) exhibit very high activity against retroviruses. This paper describes the synthesis of enantiomeric 9-(2-phosphonomethoxypropyl)adenines (I and XXVII), 9-(2-phosphonomethoxypropyl)-2,6-diaminopurines (II and XXXI), 9-(2-phosphonomethoxypropyl)guanines (III and XXIX) and 1-(R)-(2-phosphonomethoxypropyl)cytosine (XIX) by alkylation of N-protected N-(2-hydroxypropyl) derivatives of the corresponding bases with bis(2-propyl) p-toluenesulfonyloxymethylphosphonate (X), followed by stepwise N- and O-deprotection of the intermediates. The key intermediates, N-(2-hydroxypropyl) derivatives IX and XXV, were obtained by alkylation of the appropriate heterocyclic base with (R)- or (S)-2-(2-tetrahydropyranyloxy)propyl p-toluenesulfonate (VII or XXIII) and acid hydrolysis of the resulting N-[2-(2-tetrahydropyranyloxy)propyl] derivatives VIII and XXII. The chiral synthons were prepared by tosylation of (R)- or (S)-2-(2-tetrahydropyranyloxy)propanol (VI or XXI) available by reduction of enantiomeric alkyl 2-O-tetrahydropyranyllactates V and XXI with sodium bis(2-methoxyethoxy)aluminum hydride. This approach was used for the synthesis of cytosine, adenine and 2,6-diaminopurine derivatives, while compounds derived from guanine were prepared by hydrolysis of 2-amino-6-chloropurine intermediates. Cytosine derivative IXe was also synthesized by alkylation of 4-methoxy-2-pyrimidone followed by ammonolysis of the intermediate IXf.

Synthesis and Kinase Phosphorylation of 4-Deoxy-D-threohexulose

1973 ◽  
Vol 51 (7) ◽  
pp. 969-972 ◽  
Author(s):  
Clifford Raymond Haylock ◽  
Keith Norman Slessor
Keyword(s):  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Kinetic Studies ◽  
Lithium Aluminum ◽  
Substrate Complex ◽  
Acetobacter Suboxydans ◽  
Enzyme Substrate ◽  
Kinase Phosphorylation ◽  
Hydrolysis Of ◽  
Yeast Hexokinase

Synthesis of the only unknown deoxyfructose, 4-deoxy-D-threohexulose, is reported. Its preparation involved reductive lithium aluminum hydride ring opening of 3,4-anhydro-1,2:5,6-di-O-isopropylidene- D-talitol, followed by hydrolysis of the resulting epimeric deoxy diisopropylidene hexitols and selective Acetobacter suboxydans oxidation of 3-deoxy-D-arabinohexitol. Kinetic studies using 4-deoxy-D-threohexulose as substrate for yeast hexokinase support the premise that the C-4 hydroxyl is a binding group in formation of the enzyme–substrate complex. Enzymatic synthesis of 4-deoxy-D-threohexulose 6-phosphate and 4-deoxy-D-threohexulose 1,6-diphosphate has been achieved in low yield from 4-deoxy-D-threohexulose.

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