Chemistry of the Podocarpaceae. XXII. Aspects of the chemistry of Totara-8,11,13-trien-13-ol

1969 ◽  
Vol 22 (9) ◽  
pp. 1975 ◽  
Author(s):  
RC Cambie ◽  
DR Crump ◽  
RN Duve
Keyword(s):  
Sulphuric Acid ◽  
Methyl Ether ◽  
Major Product ◽  
High Yield ◽  
Lithium Aluminium Hydride ◽  
Birch Reduction ◽  
Transannular Cyclization ◽  
Lithium Aluminium ◽  
Fragmentation Reactions

Attempts have been made to effect fragmentation reactions with bromo- tetralone systems related to 6α-bromo-13-hydroxytotara-8,11,13-trien-7- one (VII), a compound which affords a secoditerpenoid (IX) when treated with DMSO-NaHCO3. On treatment with sulphuric acid in acetone, the mono- epoxide derivative (XXVIII) of the methyl ether of the secoditerpenoid undergoes a novel aromatization to a naphthalenic aldehyde (XXXI) by successive transannular cyclization and fragmentation reactions. ��� A 7β-hydroxy configuration has been confirmed for the major product from reduction of 13-acetoxytotara-8,11,13-trien-7-one (VIII) with lithium aluminium hydride. 13-Methoxytotara-8,11,13-triene (II) has been deisopropylated and then subjected to Birch reduction in an attempt to effect a high yield conversion into (+)-podocarp-8(14)-en- 13-one (XXXVII), a potentially useful intermediate for synthesis.

The synthesis of Cyclododecane-r-1,c-5,c-9-triamine and r-1,c-5,c-9-Tris(2,3-dimethoxybenzamido)cyclododecane

1975 ◽  
Vol 28 (3) ◽  
pp. 673 ◽  
Author(s):  
DJ Collins ◽  
C Lewis ◽  
JM Swan
Keyword(s):  
Aqueous Solution ◽  
Acid Hydrolysis ◽  
Sulphuric Acid ◽  
Sodium Carbonate ◽  
Sodium Azide ◽  
Room Temperature ◽  
Dimethyl Formamide ◽  
Lithium Aluminium Hydride ◽  
Lithium Aluminium ◽  
Hydrolysis Of

Treatment of cyclododecane-r-1,c-5,c-9-triyl tris(p-toluenesulphonate) with sodium azide in dimethyl-formamide at 100� for 6 h gave the corresponding cis,cis-triazide which upon hydrogenation or reduction with lithium aluminium hydride gave cyclododecane-r-1,c-5,c-9-triamine, isolated as the tris-salicylidene derivative. Acid hydrolysis of this, removal of the salicylaldehyde, and treatment of the aqueous solution with sodium carbonate and 2,3-dimethoxybenzoyl chloride gave r-1,c-5,c- 9-tris(2,3-dimethoxybenzamido)cyclododecane. ��� Treatment of (E,E,E)-cyclododeca-1,5,9-triene with an excess of acetonitrile and sulphuric acid at room temperature for three days gave 18% of (E,E)-1-acetamidocyclododeca-4,8-diene; no di- or tri-amides were isolated.

Chemistry of the Podocarpaceae. XXXIV. Some oxidation products of (13R)-Labda-8(17),14-dien-13-ol (Manool)

1971 ◽  
Vol 24 (11) ◽  
pp. 2365 ◽  
Author(s):  
RC Cambie ◽  
KN Joblin ◽  
AF Preston
Keyword(s):  
Nucleophilic Substitution ◽  
Potassium Permanganate ◽  
Hydroxy Acid ◽  
Methyl Ketone ◽  
Major Product ◽  
Oxidation Products ◽  
Lithium Aluminium Hydride ◽  
Methyl Ketones ◽  
Sodium Dichromate ◽  
Lithium Aluminium

Some products from the oxidation of manool (3) are examined. Potassium permanganate gives, inter alia, the hitherto unreported compound (16) while sodium dichromate gives the methyl ketone (5) and, as the major product, a mixture of (Z)- and (E)-α,β-unsaturated aldehydes (21). Hypoiodite oxidation of the methyl ketone (5) gives the α-hydroxy acid (26) in addition to the expected acid (6). Products of nucleophilic substitution have also been obtained from the hypoiodite oxidation of the methyl ketones (9) and (37). Peracid oxidation of the methyl ketone (5) gives the epoxy acetate (41) which, on reduction with lithium aluminium hydride, affords the diol (7), from which the odoriferous oxide (30) can be prepared. Oxidations leading to formation of the dione (10) are investigated.

4,5-Seco-4,6-cyclosteroids. I. Structure and properties of the diol from reductive rearrangement of 6β-Bromo-4β,5-epoxy-5β-cholestan-3β-ol

1969 ◽  
Vol 22 (3) ◽  
pp. 607
Author(s):  
DJ Collins ◽  
JJ Hobbs ◽  
RJ Rawson
Keyword(s):  
Physical Properties ◽  
Transformation Products ◽  
High Yield ◽  
Lithium Aluminium Hydride ◽  
Structure And Properties ◽  
Lithium Aluminium

Treatment of 6β-bromo-4β,5-epoxy-5β-cholestan-3β-ol (IV) with lithium aluminium hydride in tetrahydrofuran at reflux for 16 hr gave a high yield of a new diol, C27H48O2, formulated as 4,5-seco-4,6-cyolo-6β- cholestane-3β,5α-diol (VIIa). This assignment follows from mechanistic considerations, and the chemical and physical properties of the dial and its transformation products. ��� Stepwise removal of the oxygen functions gave the new hydrocarbon 4,5-seco-4,6-cyclo-6β-cholestane (XIXg).

Flavan derivatives. XXIII. Preparation and synthetic applications of Flav-3-enes

1968 ◽  
Vol 21 (9) ◽  
pp. 2247 ◽  
Author(s):  
JW Clark-Lewis ◽  
RW Jemison
Keyword(s):  
Sodium Borohydride ◽  
Acidic Medium ◽  
Catalytic Reduction ◽  
Heterocyclic Ring ◽  
High Yield ◽  
Lithium Aluminium Hydride ◽  
Lower Field ◽  
Field Characteristic ◽  
Lithium Aluminium ◽  
New Synthesis

2'-Hydroxychalcones and α-alkoxy-2'-hydroxychalcones are converted by sodium borohydride in isopropanol into flav-3-enes and 3-alkoxyflav-3-enes in the convenient new synthesis which makes these flavenes readily available. Catalytic reduction of the flavenes gives the corresponding flavans or 3-alkoxyflavans in high yield, and the latter are obtained mainly in the 2,s-cis-form. The flavenes immediately give flavs lium cations in the cold when treated with acids in air, and oxidation of 5,7,3',4'-tetramethoxyflav-3-ene with benzoquinone in an acidic medium gave the flavylium salt, isolated as the ferrichloride. Reduction of 5,7,3',4'-tetramethoxy-flavylium chloride with lithium aluminium hydride gave 5,7,3',4'-tetramethoxy-flav-2-ene identical with the flavene obtained from (-)-epicatechin tetramethyl ether, and confirms an earlier investigation by Gramshaw, Johnson, and King. In its N.M.R. spectrum the heterocyclic-ring protons of this flav-2-ene give an ABX multiplet which is easily distinguished from the ABX multiplet at much lower field characteristic of flav-3-enes.

4,5-Seco-4,6-cyclosteroids. III. Observations on the course of reductive rearrangement of 6β-Bromo-4β,5-epoxy-5β-cholestan-3β-ol

1969 ◽  
Vol 22 (4) ◽  
pp. 807 ◽  
Author(s):  
DJ Collins ◽  
JJ Hobbs ◽  
RJ Rawson
Keyword(s):  
Hydrogen Bromide ◽  
High Yield ◽  
Lithium Aluminium Hydride ◽  
Experimental Conditions ◽  
Lithium Aluminium ◽  
Reaction Proceeds ◽  
Derivatives Of

It has been shown that reductive rearrangement of 6β-bromo-4β,5-epoxy- 5β-cholestan-3β-ol (I) to 4,5-seco-4,6-cycle-6β-cholestane-3β,5α-diol (IXa) with lithium aluminium hydride in tetrahydrofuran proceeds via 6β-bromo-5β-cholestane-3β,5-diol (IIa). Relevant reactions of the latter and the corresponding 3-ketone are discussed. ��� Similar conversion of the 3-epimer of (I) into 4,5-seco-4,6-cyclo- 6β-cholestane-3α,5α-diol (XIIIa) in high yield indicates that reductive rearrangement of the 6β-bromo-5β-hydroxy moiety proceeds without participation of the 3-aluminate complex. Some derivatives of (XIIIa) are described. ��� Experimental conditions required for the conversion of (I) into (IXa) are defined. ��� Combined evidence indicates that the reaction proceeds in a concerted manner by essentially base-catalysed, 1,3-elimination of hydrogen bromide from diol (IIa) with 4,5-bond migration to give the formal intermediate 3β-hydroxy-4,5-seco-4,6-cyclo-6β-cholestan-5-one (VI), further reduced to (IXa).

Studies of the optically active compounds of Anacardiaceae Exudates. IV. The structures of the rearrangement products from the long chain alicyclic ketoalocohol of Tigaso oil in Alkali

1958 ◽  
Vol 11 (4) ◽  
pp. 538
Author(s):  
JA Lamberton
Keyword(s):  
Methyl Ether ◽  
Active Compound ◽  
Monomethyl Ether ◽  
Optically Active ◽  
Side Chain ◽  
Lithium Aluminium Hydride ◽  
Active Compounds ◽  
Hydride Reduction ◽  
Lithium Aluminium ◽  
Long Chain

The structure IIIa previously proposed for the β-diketone with an unsaturated side chain, obtained by the action of alkali on the optically active compound of Tigaso oil, is confirmed by the formation of methyl stearyl ketone and resorcinol monomethyl ether in the pyrolysis of the methyl ether (IV). An anomalous lithium aluminium hydride reduction of the methyl ether (IV) and other reactions are discussed. Unsuccessful attempts have been made to synthesize the tribasic acid resulting from sodium hypobromite oxidation of the β-diketone (IIIb).

scholarly journals Synthesis of olivomycose (2,6-dideoxy-3-C-methyl-L-arabino-hexose)

1969 ◽  
Vol 47 (23) ◽  
pp. 4467-4471 ◽  
Author(s):  
E. H. Williams ◽  
W. A. Szarek ◽  
J. K. N. Jones
Keyword(s):  
Wittig Reaction ◽  
High Yield ◽  
Lithium Aluminium Hydride ◽  
Ruthenium Tetroxide ◽  
Lithium Aluminium ◽  
Acid Catalyzed ◽  
Hydrolysis Of

Oxidation of methyl 4,6–O-benzylidene-2-deoxy-α-L-arabino-hexopyranoside (1) with ruthenium tetroxide gave the 3-ketone 2 in high yield. A Wittig reaction between methylenetriphenylphosphorane and compound 2 gave methyl 4,6-O-benzylidene-2,3-dideoxy-3-C-methylene-α-L-erythro-hexopyranoside (3), which was hydrated by the oxymercuration–demercuration procedure to afford methyl 4,6-O-benzylidene-2-deoxy-3-C-methyl-α-L-arabino-hexopyranoside (4). The reaction of compound 4 with N-bromosuccinimide gave methyl 4-O-benzoyl-6-bromo-2,6-dideoxy-3-C-methyl-α-L-arabino-hexopyranoside (5) in high yield. Treatment of compound 5 with lithium aluminium hydride followed by acid-catalyzed hydrolysis of the resultant product, gave L-olivomycose (6).

scholarly journals Study of lithium aluminium hydride reduction of 5-acetyl-1,6-dimethyl-4-phenyl-3,4-dihydropyrimidin-2(1h)-one

2017 ◽  
Vol 15 (1) ◽  
pp. 17-22
Author(s):  
Dragan Zlatkovic ◽  
Niko Radulovic
Keyword(s):  
Chromatographic Separation ◽  
Major Product ◽  
Lithium Aluminium Hydride ◽  
Reaction Products ◽  
Hydride Reduction ◽  
Lithium Aluminium

In this paper, we investigated the LiAlH4-reduction of 5-acetyl-1,6-dimethyl- 4-phenyl-3,4-dihydropyrimidin-2(1H)-one (N-methylated Biginelli compound). Following the reduction and SiO2-promoted dehydration, (Z)-5-ethylidene-1-methyl-6- methylene-4-phenyltetrahydropyrimidin-2(1H)-one was isolated as the major product (33% yield). Chromatographic separation of the reaction products also allowed us to isolate (yield in parentheses) and fully spectrally characterize: 1,6-dimethyl-4-phenyl- 5-vinyl-3,4-dihydropyrimidin-2(1H)-one (20%), 5-ethyl-1,6-dimethyl-4-phenyl-3,4- dihydro-pyrimidin-2(1H)-one (9%), 5-(1-hydroxyethyl)-1,6-dimethyl-4-phenyl-3,4- dihydropyrimidin-2(1H)-one (5%). A possible mechanism explaining the formation of these products is proposed.

Synthesis of Carba Analogues of Deoxy-4-C-(hydroxymethyl)pentofuranoses, Intermediates in the Synthesis of Carbocyclic Nucleosides

1998 ◽  
Vol 63 (12) ◽  
pp. 2044-2064 ◽  
Author(s):  
Hubert Hřebabecký ◽  
Milena Masojídková ◽  
Antonín Holý
Keyword(s):  
Allyl Alcohol ◽  
Major Product ◽  
Protecting Groups ◽  
Carbocyclic Nucleosides ◽  
Lithium Aluminium Hydride ◽  
Lithium Aluminium ◽  
Benzoyl Group ◽  
Glucose Reduction ◽  
Hydroxy Groups

Racemic dimethyl 4-methoxy- (11 and 12), diallyl 4-allyloxy- (13 and 14) and dimethyl 4-(ethylsulfanyl)-2-hydroxycyclopentane-1,1-dicarboxylates (15 and 16) were prepared by base-catalyzed addition of methanol, allyl alcohol and ethylsulfane, respectively, to dimethyl (4-oxobut-2-en-1-yl)malonate (6). Deallylation of 13 and 14 afforded 4-hydroxycyclopentanes 27 and 28. Reduction of 11-16 with lithium aluminium hydride gave the corresponding 4-substituted 2,2-bis(hydroxymethyl)cyclopentanols. Dimethyl (2S,3S,4R)-, (2R,3S,4R)-3-benzyloxy-4-formyloxy-2-hydroxycyclopentane-1,1-dicarboxylates (35, 36) and dimethyl (2S,3S,4R)-, (2R,3S,4R)-3-benzyloxy-2-benzoyloxy-4-methoxycyclopentane-1,1-dicarboxylates (39, 40) were synthesized starting from D-glucose. Reduction of dimethyl cyclopentane-1,1-dicarboxylates 39 and 40 with lithium aluminium hydride, benzoylation of the formed hydroxy derivatives, hydrogenolysis of benzyl groups, conversion of the liberated hydroxy groups into dithiocarbonates and their reduction with tributylstannane afforded, after removal of the protecting groups, (2R,4R)-1,1-bis(hydroxymethyl)-4-methoxycyclopentan-2-ol ((2R,4R)-17) and (3R,4R)-1,1-bis(hydroxymethyl)-4-methoxycyclopentan-3-ol (51). Reduction of a mixture of esters 35 and 36 gave (2R,3R)-2-benzyloxy-5-(hydroxymethyl)hexane-1,3,6-triol (52) as the major product and (2R,3S,4R)-3-benzyloxy-1,1-bis(hydroxymethyl)cyclopentane-2,4-diol (53) as the minor product. The latter was converted into (3R,4R)-1,1-bis(hydroxymethyl)cyclopentane-3,4-diol (58). 3-Deoxycarba analogues 51 and 58 arose by migration of benzoyl group in the preparation of the dithiocarbonates.

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