6153-05-5

Usage

InChI:InChI=1/C6H8O/c1-3-6(2)4-5-7/h1,4,7H,5H2,2H3/b6-4-

Synthetic route

3-methyl-1-penten-4-yn-3-ol (3230-69-1) → (Z)-3-methylpent-2-en-4-ynol (6153-05-5) + (E)-3-methylpent-2-en-4-yn-1-ol (6153-06-6)

Conditions	Yield
acid Allylic Rearrangement;	A 85% B 15%
With sulphurous acid at 50℃; for 2h; Isomerization;	A 81% B n/a
With sulfuric acid; hydroquinone In di-isopropyl ether at 50 - 52℃; for 2h;	A 73.7% B 14.1%

3-methyl-1-penten-4-yn-3-ol (3230-69-1) → (E)-1-bromo-3-methylpent-2-en-4-yne (69371-58-0) + (Z)-3-methylpent-2-en-4-ynol (6153-05-5)

Conditions	Yield
With hydrogen bromide; hydroquinone In di-isopropyl ether at 50 - 52℃; for 8h;	A 59.6% B 19.3%

(Z)-3-methyl-5-trimethylsilylpent-2-en-4-yn-1-ol (121635-19-6) → (Z)-3-methylpent-2-en-4-ynol (6153-05-5)

Conditions	Yield
With methanol; potassium carbonate at 20℃;	58%
With potassium carbonate In methanol

3-methyl-1-penten-4-yn-3-ol (3230-69-1) → (Z)-3-methylpent-2-en-4-ynol (6153-05-5) + cis-3-methyl-5-nitroxy-3-penten-1-yne + trans-3-methyl-5-nitroxy-3-penten-1-yne

Conditions	Yield
With nitric acid; hydroquinone In di-isopropyl ether at 50 - 52℃; for 7h;	A 16.1% B 56.4% C 13%

3-methyl-1-penten-4-yn-3-ol (3230-69-1) → (Z)-3-methylpent-2-en-4-ynol (6153-05-5)

Conditions	Yield
With sulfuric acid; water at 20℃; for 48h;	56%
With water at 70℃;	13%
With sulfuric acid for 20h;

5-Trimethylsilyl-3-methyl-pent-1-en-4-in-3-ol (50516-66-0) → (Z)-3-methylpent-2-en-4-ynol (6153-05-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: K2CO3, MeOH 2: H2O, H2SO4 View Scheme
Multi-step reaction with 2 steps 1: K2CO3 / methanol 2: 10percent H2SO4 View Scheme

(E)-3-methylpent-2-en-4-yn-1-ol (6153-06-6) → (Z)-3-methylpent-2-en-4-ynol (6153-05-5)

Conditions	Yield
With benzophenone In acetonitrile for 0.333333 - 4h; Product distribution / selectivity; UV-irradiation; Microwave irradiation;
With bis(p-dimethylaminophenyl)methanone In acetonitrile for 0.333333 - 2h; Product distribution / selectivity; UV-irradiation; Microwave irradiation;
With benzophenone In acetonitrile at 25℃; for 1h; Product distribution / selectivity; UV-irradiation;
With iodine In acetonitrile at 200℃; under 15001.5 Torr; for 1.01667h; Product distribution / selectivity; UV-irradiation; Microwave irradiation;

3-methyl-2-penten-4-yn-1-al (53635-18-0) → (Z)-3-methylpent-2-en-4-ynol (6153-05-5) + (E)-3-methylpent-2-en-4-yn-1-ol (6153-06-6)

Conditions	Yield
With sodium tetrahydroborate In ethanol at 25℃; for 3h; Overall yield = 95 %;

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) → 2,3-dimethylfuran (14920-89-9)

Conditions	Yield
With [Au2Cl2(μ-1,1′-bis(ditert-butylphosphino)ferrocene)] In chloroform-d1; 1,2-dichloro-ethane at 20℃; for 3h; Catalytic behavior; Reagent/catalyst; Inert atmosphere;	100%
With CuCl2*2H2O	98%
With trimethyl-4,6,9 hexaza-1,3,4,6,7,9 phospha-5 tricyclo<3.3.1.13,7>decane; [{IrCl(μ-Cl)(η4-cod)}2] In water at 80℃; for 1h;	96%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) → 3-methyl-1-penten-4-yn-3-ol (3230-69-1)

Conditions	Yield
With sulfuric acid; hydroquinone; mercury dichloride In di-isopropyl ether at 50 - 52℃; for 0.166667h; Product distribution;	100%

vinyl acetate (108-05-4) + (Z)-3-methylpent-2-en-4-ynol (6153-05-5) → (Z)-3-Methyl-2-penten-4-in-1-ylacetat (35272-87-8)

Conditions	Yield
With hexamethyltriamido-N-benzylimidophosphate In tetrahydrofuran at 20℃; for 15h; Acylation;	99%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 6-iodo-2,2-dimethyl-3,4-dihydronaphthalen-1(2H)-one → (Z)-1-(5-hydroxy-3-methylpent-3-en-1-yn-1-yl)-6-iodo-2,2-dimethyl-1,2,3,4-tetrahydronaphthalen-1-ol

Conditions	Yield
Stage #1: (Z)-3-methylpent-2-en-4-ynol With n-butyllithium In tetrahydrofuran at -80℃; for 0.75h; Stage #2: 6-iodo-2,2-dimethyl-3,4-dihydronaphthalen-1(2H)-one In tetrahydrofuran at -80 - 20℃; for 1.16667h;	99%

3,4-dihydro-2H-pyran (110-87-2) + (Z)-3-methylpent-2-en-4-ynol (6153-05-5) → (Z)-3-Methyl-2-penten-4-ynyl tetrahydropyranyl ether (41967-81-1)

Conditions	Yield
With pyridinium p-toluenesulfonate In dichloromethane at 0℃; for 3h;	98%
With pyridinium p-toluenesulfonate In dichloromethane for 2h; Ambient temperature;	96%
With toluene-4-sulfonic acid In diethyl ether at 20℃;	87%
With toluene-4-sulfonic acid at 20℃; for 0.75h;

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 4-Hex-1-ynyl-4,5,5-trimethyl-[1,3]dioxolan-2-one → (Z)-6-Butyl-3,8,9-trimethyl-deca-2,6,7-trien-4-yne-1,9-diol

Conditions	Yield
With diethylamine; potassium bromide; copper(l) iodide; tetrakis(triphenylphosphine) palladium(0) In tetrahydrofuran Ambient temperature;	97%

heptanal (111-71-7) + (Z)-3-methylpent-2-en-4-ynol (6153-05-5) → (Z)-3-Methyl-2-dodecen-4-yne-1,6-diol

Conditions	Yield
With n-butyllithium In tetrahydrofuran; hexane	97%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + trimethyl orthoformate (149-73-5) → (Z)-5-Dimethoxymethoxy-3-methyl-pent-3-en-1-yne (118328-41-9)

Conditions	Yield
With magnesium chloride In dichloromethane at 25℃; for 2h;	96%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 7,7-dimethyl-2-phenyl-6,7-dihydroquinoline-5,8-dione → (Z)-5-hydroxy-5-(5′-hydroxy-3-methylpent-3′-en-1′-yn-1′-yl)-7,7-dimethyl-2-phenyl-6,7-dihydroquinolin-8(5H)-one

Conditions	Yield
Stage #1: (Z)-3-methylpent-2-en-4-ynol With n-butyllithium In tetrahydrofuran at -78℃; for 1h; Inert atmosphere; Stage #2: 7,7-dimethyl-2-phenyl-6,7-dihydroquinoline-5,8-dione In tetrahydrofuran at -78 - 20℃; for 2.5h; Inert atmosphere; regioselective reaction;	96%
Stage #1: (Z)-3-methylpent-2-en-4-ynol With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1h; Inert atmosphere; Stage #2: 7,7-dimethyl-2-phenyl-6,7-dihydroquinoline-5,8-dione In tetrahydrofuran; hexane at -78 - 20℃; for 17h; Inert atmosphere; regioselective reaction;	79%

iodobenzene (591-50-4) + (Z)-3-methylpent-2-en-4-ynol (6153-05-5) → (Z)-3-methyl-5-phenyl-2-penten-4-yn-1-ol (148802-08-8)

Conditions	Yield
copper(l) iodide; tetrakis(triphenylphosphine) palladium(0) In various solvent(s) 15 min, 0 deg C; 30 min, RT;	95%
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide for 2h; Ambient temperature;	93%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + benzoyl chloride (98-88-4) → Benzoic acid (Z)-3-methyl-pent-2-en-4-ynyl ester (210236-01-4)

Conditions	Yield
With pyridine In dichloromethane 1.) 0 deg C, 2 h, 2.) room temperature, 16 h;	95%
With triethylamine	91%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) → 3-methyl-2-methylene-2, 5-dihydrofuran

Conditions	Yield
With silver carbonate In benzene-d6 at 20℃; for 2h; Cyclization;	95%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + chlorodimethyl(1,1,2-trimethylpropyl)silane (67373-56-2) → (Z)-[(2,3-dimethyl-2-butyl)dimethylsilyloxy]-3-methylpent-2-en-4-yne (196600-08-5)

Conditions	Yield
With 1H-imidazole In dichloromethane at 0℃; for 18h;	93%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 2,2-dimethyl-6-pentyl-3,4-dihydronaphthalen-1(2H)-one → (Z)-1-(5-hydroxy-3-methylpent-3-en-1-yn-1-yl)-2,2-dimethyl-6-pentyl-1,2,3,4-tetrahydronaphthalen-1-ol

Conditions	Yield
Stage #1: (Z)-3-methylpent-2-en-4-ynol With n-butyllithium In tetrahydrofuran at -80℃; for 0.666667h; Inert atmosphere; Stage #2: 2,2-dimethyl-6-pentyl-3,4-dihydronaphthalen-1(2H)-one In tetrahydrofuran at -80 - 20℃; for 0.666667h; Inert atmosphere;	93%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 2-methyl-4-(2,6,6-trimethylcyclohex-1-en-1-yl)-2-butenal (3155-71-3) → 2Z,7E-3,7-dimethyl-9-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,7-nonadiene-4-yne-1,6-diol (50895-68-6)

Conditions	Yield
Stage #1: (Z)-3-methylpent-2-en-4-ynol With 2-Methoxypropene; toluene-4-sulfonic acid at 0℃; for 0.5h; Stage #2: With triethylamine at 20℃; Stage #3: 2-methyl-4-(2,6,6-trimethylcyclohex-1-en-1-yl)-2-butenal Reagent/catalyst; Further stages;	92.2%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + {4-[2-Bromo-1-(2-methoxy-ethoxymethoxy)-cyclopent-2-enyl]-but-2-ynyloxy}-tert-butyl-dimethyl-silane (131318-35-9) → (Z)-5-[5-[4-(tert-Butyl-dimethyl-silanyloxy)-but-2-ynyl]-5-(2-methoxy-ethoxymethoxy)-cyclopent-1-enyl]-3-methyl-pent-2-en-4-yn-1-ol (131318-37-1)

Conditions	Yield
With propylamine; copper(l) iodide; tetrakis(triphenylphosphine) palladium(0)	92%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 4,4,5-Trimethyl-5-prop-1-ynyl-[1,3]dioxolan-2-one → (Z)-3,6,8,9-Tetramethyl-deca-2,6,7-trien-4-yne-1,9-diol

Conditions	Yield
With diethylamine; potassium bromide; copper(l) iodide; tetrakis(triphenylphosphine) palladium(0) In tetrahydrofuran Ambient temperature;	92%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 4-methoxy-benzoyl chloride (100-07-2) → (Z)-3-methylpent-2-en-4-yn-1-yl 4-methoxybenzoate

Conditions	Yield
With triethylamine In dichloromethane at 25℃; for 14h; Inert atmosphere; Darkness;	92%
With triethylamine In dichloromethane at 25℃; for 1h;	89%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + tert-butylchlorodiphenylsilane (58479-61-1) → (2Z)-1-tert-butyldiphenylsilyloxy-3-methylpent-2-en-4-yne

Conditions	Yield
With 1H-imidazole In N,N-dimethyl-formamide at 20℃;	92%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) → cis-2,3-epoxy-3-methylpent-4-ynol

Conditions	Yield
With disodium hydrogenphosphate; 3-chloro-benzenecarboperoxoic acid In dichloromethane for 2h;	91%
With 3-chloro-benzenecarboperoxoic acid In dichloromethane 1.) 0 deg C, 30 min, 2.) room temperature, 13 h;	62%
With sodium hydrogencarbonate; 3-chloro-benzenecarboperoxoic acid In dichloromethane Epoxidation;

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + acetylenedicarboxylic acid diethyl ester (762-21-0) → 1,6-dimethyl-7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylic acid diethyl ester (1261167-88-7)

Conditions	Yield
With C49H42Au2Cl2N2O4P4S2 In glycerol at 45℃; for 4h; Solvent; Green chemistry;	91%
With bis(1,5-cyclooctadiene)diiridium(I) dichloride at 20℃; for 4h; Inert atmosphere;	81%

ethyl bromide (74-96-4) + (Z)-3-methylpent-2-en-4-ynol (6153-05-5) + propargyl bromide (106-96-7) → (Z)-3-methylocta-2-en-4,7-diyn-1-ol

Conditions	Yield
Stage #1: ethyl bromide With iodine; magnesium In tetrahydrofuran at 50℃; Inert atmosphere; Stage #2: (Z)-3-methylpent-2-en-4-ynol In tetrahydrofuran at 50℃; Inert atmosphere; Stage #3: propargyl bromide Further stages;	91%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 2,2,3,3-tetramethyl-2,3-dihydronaphthalene-1,4-dione → (Z)-(1′-hydroxy-2′,2′,3′,3′-tetramethyl-4′-oxo-tetrahydronaph-thalene-one-yl)-3-methylpentyl-2-en-4-yn-1-ol

Conditions	Yield
Stage #1: (Z)-3-methylpent-2-en-4-ynol With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1h; Inert atmosphere; Stage #2: 2,2,3,3-tetramethyl-2,3-dihydronaphthalene-1,4-dione In tetrahydrofuran; hexane at -78 - 20℃; for 16h;	91%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 6,6-dimethyl-5,6-dihydrobenzofuran-4,7-dione → C16H18O4

Conditions	Yield
Stage #1: (Z)-3-methylpent-2-en-4-ynol With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1h; Inert atmosphere; Stage #2: 6,6-dimethyl-5,6-dihydrobenzofuran-4,7-dione In tetrahydrofuran; hexane at -78 - 20℃; for 17h; Inert atmosphere; regioselective reaction;	90%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + 4-methoxy-phenol (150-76-5) → (Z)-(4-methoxyphenoxy)-3-methylpent-2-en-4-yne (196600-09-6)

Conditions	Yield
With di-isopropyl azodicarboxylate; triphenylphosphine for 4h; Ambient temperature;	89%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + dimethyl acetylenedicarboxylate (762-42-5) → 1,6-dimethyl-7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylic acid dimethyl ester (63098-21-5)

Conditions	Yield
With C49H42Au2Cl2N2O4P4S2 In glycerol at 45℃; for 4h; Green chemistry;	89%
With bis(1,5-cyclooctadiene)diiridium(I) dichloride at 20℃; for 4h; Inert atmosphere;	83%

(Z)-3-methylpent-2-en-4-ynol (6153-05-5) + C12H11BrO2 → (Z)-7-bromo-4-hydroxy-4-(5′-hydroxy-3-methylpent-3′-en-1′-yn-1′-yl)-2,2-dimethyl-3,4-dihydronaphthalen-1(2H)-one

Conditions	Yield
Stage #1: (Z)-3-methylpent-2-en-4-ynol With n-butyllithium In tetrahydrofuran at -78℃; for 1h; Inert atmosphere; Stage #2: C12H11BrO2 In tetrahydrofuran at -78 - 20℃; for 2.5h; Inert atmosphere; regioselective reaction;	89%
Stage #1: (Z)-3-methylpent-2-en-4-ynol With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1h; Inert atmosphere; Stage #2: C12H11BrO2 In tetrahydrofuran; hexane at -78 - 20℃; for 17h; Inert atmosphere; regioselective reaction;	70%

Upstream product

• 3230-69-1 3-methyl-1-penten-4-yn-3-ol 
• 121635-19-6 (Z)-3-methyl-5-trimethylsilylpent-2-en-4-yn-1-ol 
• 50516-66-0 5-Trimethylsilyl-3-methyl-pent-1-en-4-in-3-ol 
• 6153-06-6 (E)-3-methylpent-2-en-4-yn-1-ol 
• 53635-18-0 3-methyl-2-penten-4-yn-1-al 

Downstream Products

• 6153-06-6 (E)-3-methylpent-2-en-4-yn-1-ol 
• 187409-93-4 1-(5-hydroxy-3-methyl-pent-3-en-1-ynyl)-2,2,6-trimethyl-cyclohexanol 
• 50895-68-6 2Z,7E-3,7-dimethyl-9-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,7-nonadiene-4-yne-1,6-diol 
• 79-80-1 vitamin A₂ 
• 94761-66-7 11-Dehydro-13-cis-vitamin A⁽²⁾ 
• 62030-09-5 (4-chloro-benzoylamino)-phenyl-acetic acid (Z)-3-methyl-pent-2-en-4-ynyl ester 
• 130584-04-2 (+)-1(Z)-(1R,4R,6S)-4-tert-butyldimethylsiloxy-1-(5-hydroxy-3-methylpent-3-en-1-ynyl)-2,2,6-trimethylcyclohexanol 
• 130584-04-2 (4R,6R)-4-(tert-Butyl-dimethyl-silanyloxy)-1-((Z)-5-hydroxy-3-methyl-pent-3-en-1-ynyl)-2,2,6-trimethyl-cyclohexanol 
• 150807-03-7 (2Z,8S,9R)-10-(tert-butyldiphenylsilyloxy)-8,9-epoxy-3-methyl-4,6-decadiyn-2-en-1-ol 
• 124743-93-7 (2Z)-5-(4-Methoxy-2,3,6-trimethylphenyl)-3-methylpent-2-en-4-in-1-ol 
• 14920-89-9 2,3-dimethylfuran 
• 3230-69-1 3-methyl-1-penten-4-yn-3-ol 
• 148802-08-8 (Z)-3-methyl-5-phenyl-2-penten-4-yn-1-ol 
• 178766-79-5 (Z)-3-Methyl-6-<(Z)-2-<(trimethylsilyl)ethynyl>-2-cyclohexen-1-ylidene>-2-hexen-4-yn-1-ol 

Relevant academic research and scientific papers

Synthetic study of an intermediate towards paracentrone

Paracentrone (1), the second naturally occurring C31-methyl ketone apocarotenoid from fucoxanthin (2), was first isolated from the sea urchin Paracentrotus lividus. In this study, we focused on this carotenoid metabolite and report on a synthetic approach towards (3E)-(5R)-[(2R,4S)-2-hydroxy-4-(tert-butyldimethylsilyl)oxy-2,6,6-trimethylcyclohexylidene]-1-iodo-4-methyl-1,3, 5-hexatriene (5), a synthetic intermediate towards 1. This was obtained from epoxy acetylene (11) via (2E)-(4R)-[(2R,4S)-2-hydroxy-4-(tert-butyldimethyl-silyl)oxy-2,6,6-trimethylcyclohexylidene]-3-methylpenta-2,4-dien-1-ol (7).

Discovery of a Potent Free Fatty Acid 1 Receptor Agonist with Low Lipophilicity, Low Polar Surface Area, and Robust in Vivo Efficacy

The free fatty acid receptor 1 (FFA1 or GPR40) is established as an interesting potential target for treatment of type 2 diabetes. However, to obtain optimal ligands, it may be necessary to limit both lipophilicity and polar surface area, translating to a need for small compounds. We here describe the identification of 24, a potent FFA1 agonist with low lipophilicity and very high ligand efficiency that exhibit robust glucose lowering effect.

A method of product yield allylol cis

The invention relates to a method for improving the yield of an allyl alcohol maleinoid form product, the formula (1) are isomerized into a mixture of the formula (2) and the formula (3), the formula (1), the formula (2) and the formula (3) are selected from alkyl, aryl and alkaryl, R2 is selected from H, alkyl and aryl, in a solvent and with the existence of a heterogeeous acid catalyst, the formula (1) is subjected to reaction, the solvent is water or a multiphase solvent system which comprises an aqueous phase and an organic solvent phase, and the organic solvent phase comprises an organic solvent which is selected from ethers, ketone or saturated fat hydrocarbon or a mixture of the same and is unmixed with water, the formula (1) is subjected to allylic rearrangement reaction, and a certain proportion of formula (3) is added into the allylic rearrangement reaction system of the formula (1); the gaseous phase interior label content of the formula (3) is greater than 95%. According to the invention, the forming of the product maleinoid form (2) is facilitated, the proportion of the maleinoid form (2) to the transform (3) is enhanced, and the yield of the maleinoid form (2) can be improved by about 13% compared with an original system.

Synthesis of C6 acetylenic alcohols

C6 acetylenic alcohols are important intermediates in the synthesis of Vitamin A and carotenoids. New synthesis methods of the C6 acetylenic alcohols and their four derivatives are reported. These designed synthesis methods are useful improvement to the present methodologies. Structures of these compounds are confirmed by 1H NMR, IR and mass spectra analysis.

ORTHO-FLUORO SUBSTITUTED COMPOUNDS FOR THE TREATMENT OF METABOLIC DISEASES

There is provided novel fluoro-substituted compounds capable of modulating the G- protein-coupled receptor GPR40, compositions comprising the compounds, and methods for their use for controlling insulin levels in vivo and for the treatment of conditions such as type II diabetes, hypertension, ketoacidosis, obesity, glucose intolerance, and hypercholesterolemia and related disorders associated with abnormally high or low plasma lipoprotein, triglyceride or glucose levels.

Intramolecular pyridone/enyne photocycloaddition: Partitioning of the [4 + 4] and [2 + 2] pathways

Chemical equations presented. Intramolecular photocycloaddition (>290 nm) between a 1,3-enyne and a 2-pyridone is far more selective than the intermolecular version; a three-atom linkage both controls regiochemistry and separates the [2 + 2] and [4 + 4] pathways. All four head-to-head, head-to-tail, tail-to-head, and tail-to-tail tetherings have been investigated. Linkage via the ene of the enyne leads to [2 + 2] products regardless of alkene geometry, whereas linkage through the yne results in [4 + 4] cycloadducts. The bridged 1,2,5-cyclooctatriene products of [4 + 4] cycloaddition are unstable and undergo a subsequent [2 + 2] dimerization reaction.

PHOTOCHEMICAL ISOMERIZATION OF A PENT-2-EN-4-YN-1-OL

The present invention relates to a process for photochemically isomerizing an E-pent-2-en-4-yn-1-ol to a Z-pent-2-en-4-yn-1-ol and vice versa.

Process for the rearrangement of allyl alcohols

The present invention is directed to a process for isomerizing a pent-1-en-3-ol according to formula (1) to a mixture of the stereoisomers Z-pent-2-en-1-ol (2) and E-pent-2-en-1-ol (3) according to formulae (2) and (3) wherein R1 is selected from alkyl, aryl, and alkylaryl radicals, R2 is selected from H, alkyl, and aryl radicals; which process comprises reacting the pent-1-en-3-ol (1) in a solvent and in the presence of a heterogeneous acid catalyst. The heterogeneous acid catalyst is preferably selected from the group consisting of Br?nsted acids on a carrier, strong acidic cation exchangers and polymers having acidic groups. The products of the process according to the present invention are important intermediates for the manufacture of isoprenoids such as vitamin A and derivatives thereof and carotenoids.

PROCESS FOR ISOMERIZING A PENT-1-EN-3-OL

The present invention relates to a process for isomerizing a pent-1-en-3-ol to a mixture of the isomers Z-pent-2-en-1-ol and E-pent-2-en-1-ol by reacting the pent-1-en-3-ol (1) in a multiphase system comprising an aqueous phase and an organic solvent phase, and in the presence of an acid catalyst which is not a cation exchanger, wherein the organic solvent phase comprises a water-immiscible organic solvent.

Synthesis of pluraflavin A "aglycone"

The "aglycone" of pluraflavin A (2) has been synthesized. The key features of this synthesis include a 1,3-dipolar cycloaddition between a nitrile oxide (cf. 14) and an olefin (22) to yield an isoxazoline followed by subsequent conversion into the γ-pyrone of pluraflavin A. The epoxide moiety linked to the pyrone is installed prior to Diels-Alder installation of the D ring, which allows access to a number of potentially active cytotoxic intermediates en route to the final compound. The preliminary in vitro results of two such compounds are also included with the racemic title compound exhibiting cytotoxicity in the nanomolar range.