7235-40-7

Usage

InChI:InChI=1/C40H56/c1-31(19-13-21-33(3)25-27-37-35(5)23-15-29-39(37,7)8)17-11-12-18-32(2)20-14-22-34(4)26-28-38-36(6)24-16-30-40(38,9)10/h11-14,17-22,25-28H,15-16,23-24,29-30H2,1-10H3/b12-11+,19-13+,20-14+,27-25+,28-26u,31-17-,32-18+,33-21-,34-22+

Synthetic route

(2E,4E,6E)-2,7-dimethyl-2,4,6-octatrienedial (5056-17-7) + (1E)-1-(2,6,6-trimethylcyclohex-1-enyl)-3-methyl-1,4-pentadien-3-ol (59057-30-6) + triphenylphosphine (603-35-0) → beta-carotene (7235-40-7)

Conditions	Yield
Stage #1: (1E)-1-(2,6,6-trimethylcyclohex-1-enyl)-3-methyl-1,4-pentadien-3-ol; triphenylphosphine With hydrogenchloride In methanol; water at 45℃; for 1h; Stage #2: (2E,4E,6E)-2,7-dimethyl-2,4,6-octatrienedial With 1,2-bis (3-methylimidazolium-1-yl) ethane dihydroxide; sodium carbonate In methanol; water at 20℃; for 3h; Reagent/catalyst; Temperature; Wittig Olefination; Inert atmosphere;	95%

Retinol acetate (127-47-9) → beta-carotene (7235-40-7)

Conditions	Yield
Stage #1: Retinol acetate With sulfuric acid; triphenylphosphine In methanol at 0 - 5℃; for 10.5h; Stage #2: With palladium diacetate; β‐cyclodextrin In ethanol; dichloromethane; water under 16501.7 Torr; for 8h; Reagent/catalyst; Solvent; Pressure; Temperature; Autoclave;	90.6%
Stage #1: Retinol acetate With aniline In ethanol Stage #2: With hydrogenchloride; triphenylphosphine In ethanol; water at 10 - 25℃; for 26h; Reagent/catalyst; Solvent; Further stages;	58.75%

C35H48Si + 2-[(1’E,3’E)-3’-methyl-4’-iodobuta-1’,3’-dien-1’yl]-1,3,3-trimethylcyclohex-1-ene (138846-06-7) → beta-carotene (7235-40-7)

Conditions	Yield
Stage #1: C35H48Si With tetrabutyl ammonium fluoride In tetrahydrofuran at 0℃; for 0.5h; Inert atmosphere; Stage #2: 2-[(1’E,3’E)-3’-methyl-4’-iodobuta-1’,3’-dien-1’yl]-1,3,3-trimethylcyclohex-1-ene With tris(dibenzylideneacetone)dipalladium(0) chloroform complex In tetrahydrofuran at 0 - 25℃; for 1.25h; Inert atmosphere;	90%

(2E,4E,6E,8E,10E,12E,14E)-2,15-diiodo-6,11-dimethylhexadeca-2,4,6,8,10,12,14-heptaene (1427286-50-7) + tributyl [(E)-2-(2,6,6-trimethylcyclohex-1-en-1-yl)ethenyl]stannane (1427286-52-9, 791131-03-8) → beta-carotene (7235-40-7)

Conditions

Yield

Stage #1: (2E,4E,6E,8E,10E,12E,14E)-2,15-diiodo-6,11-dimethylhexadeca-2,4,6,8,10,12,14-heptaene; tributyl [(E)-2-(2,6,6-trimethylcyclohex-1-en-1-yl)ethenyl]stannane With tetrakis(triphenylphosphine) palladium(0); copper(I) thiophene-2-carboxylate; Tetrabutylammoniumsalz der Diphenylphosphinsaeure In N,N-dimethyl-formamide at 25℃; Stille Cross Coupling; Inert atmosphere; Stage #2: With 2,6-di-tert-butyl-4-methyl-phenol In diethyl ether; N,N-dimethyl-formamide; toluene at 25℃; Inert atmosphere;

86%

5,14-bis(benzenesulfonyl)-3,7,12,16-tetramethyl-1,18-bis(2,6,6-trimethyl-1-cyclohexenyl)octadeca-1,3,9,15,17-pentaene-6,13-diol bis(methoxymethyl) ether (870636-68-3) → beta-carotene (7235-40-7) + 13-cis-β,β-carotene

Conditions	Yield
With potassium methanolate In cyclohexane at 80℃; for 16h;	A 84% B n/a

5,14-bis(benzenesulfonyl)-3,7,12,16-tetramethyl-1,18-bis(2,6,6-trimethyl-1-cyclohexenyl)octadeca-1,3,9,15,17-pentaene-6,13-diol bis(methoxymethyl) ether (870636-68-3) → beta-carotene (7235-40-7) + (11Z)-β,β-carotene (18526-49-3)

Conditions	Yield
With potassium methanolate In cyclohexane at 80℃; for 16h; Product distribution / selectivity;	A 84% B n/a

1,9,18-tris(benzenesulfonyl)-3,7,12,16-tetramethyl-1,18-bis(2,6,6-trimethyl-1-cyclohexen-1-yl)-3,7,11,15-octadecatetraene-2,17-diol, bis(tetrahydropyranyl) ether → beta-carotene (7235-40-7)

Conditions	Yield
With potassium methanolate In cyclohexane; benzene at 70 - 80℃; for 18h;	81%
With potassium methanolate In cyclohexane; benzene at 70 - 80℃; for 18h; Product distribution / selectivity;	81%

11,20-dibenzenesulfonyl-11,12,19,20-tetrahydro-β-carotene (251291-82-4) → beta-carotene (7235-40-7)

Conditions	Yield
With sodium In ethanol for 10h; desulfonation; Heating;	75%
With sodium In ethanol for 10h; Heating / reflux;	75%

11,20-di(benzenesulfonyl)-11,12,19,20-tetrahydro-β-carotene → beta-carotene (7235-40-7)

Conditions	Yield
With sodium In ethanol; toluene	75%

2-[(1’E,3’E)-3’-methyl-4’-iodobuta-1’,3’-dien-1’yl]-1,3,3-trimethylcyclohex-1-ene (138846-06-7) + (1E,3E,5E,7E,9E)-1,10-bis(tri-n-butylstannyl)-3,8-dimethyldeca-1,3,5,7,9-pentaene → beta-carotene (7235-40-7)

Conditions	Yield
With 2,6-di-tert-butyl-4-methyl-phenol; N-ethyl-N,N-diisopropylamine; bis(benzonitrile)palladium(II) dichloride In tetrahydrofuran; N,N-dimethyl-formamide at 20℃; for 16h; Stille cross-coupling;	73%

(2E,4E,6E,8E,10E,12E,14E)-2,15-diiodo-6,11-dimethylhexadeca-2,4,6,8,10,12,14-heptaene (1427286-50-7) + (E)-4,4,5,5-tetramethyl-2-(2-(2,6,6-trimethylcyclohex-1-enyl)-vinyl)-1,3,2-dioxaborolane (256518-16-8) → beta-carotene (7235-40-7)

Conditions

Yield

Stage #1: (2E,4E,6E,8E,10E,12E,14E)-2,15-diiodo-6,11-dimethylhexadeca-2,4,6,8,10,12,14-heptaene With tetrakis(triphenylphosphine) palladium(0); 2,6-di-tert-butyl-4-methyl-phenol In tetrahydrofuran; toluene at 25℃; for 0.0833333h; Suzuki Coupling; Inert atmosphere; Stage #2: (E)-4,4,5,5-tetramethyl-2-(2-(2,6,6-trimethylcyclohex-1-enyl)-vinyl)-1,3,2-dioxaborolane With thallium(I) hydroxide In tetrahydrofuran; water; toluene at 25℃; for 4h; Suzuki Coupling; Inert atmosphere;

73%

1,9,18-tris(benzenesulfonyl)-3,7,12,16-tetramethyl-1,18-bis(2,6,6-trimethyl-1-cyclohexen-1-yl)-3,7,11,15-octadecatetraene-2,17-diol, bis(methoxymethyl) ether → beta-carotene (7235-40-7)

Conditions	Yield
With potassium methanolate In cyclohexane; benzene at 70 - 80℃; for 18h;	71%
With potassium methanolate In cyclohexane; benzene at 70 - 80℃; for 18h; Product distribution / selectivity;	71%

5,14-bis(benzenesulfonyl)-3,7,12,16-tetramethyl-1,18-bis(2,6,6-trimethyl-1-cyclohexenyl)octadeca-1,3,9,15,17-pentaene-6,13-diol bis(1-ethoxyethyl) ether (870636-67-2) → beta-carotene (7235-40-7) + 13-cis-β,β-carotene

Conditions	Yield
With potassium methanolate In cyclohexane at 80℃; for 16h;	A 70% B n/a

1,9,18-tris(benzenesulfonyl)-3,7,12,16-tetramethyl-1,18-bis(2,6,6-trimethyl-1-cyclohexen-1-yl)-3,7,11,15-octadecatetraene-2,17-diol, bis(1-ethoxyethyl) ether → beta-carotene (7235-40-7)

Conditions	Yield
With potassium methanolate In cyclohexane; benzene at 70 - 80℃; for 17h;	70%
With potassium methanolate In cyclohexane; benzene at 70 - 80℃; for 17h; Product distribution / selectivity;	70%

all-(E)-5,14-bis(benzenesulfonyl)-3,7,12,16-tetramethyl-1,18-bis(2,6,6-trimethyl-1-cyclohexenyl)octadeca-1,3,9,15,17-pentene-6,13-diol bis(1-ethoxyethyl)ether → beta-carotene (7235-40-7) + (11Z)-β,β-carotene (18526-49-3)

Conditions	Yield
With potassium methanolate In cyclohexane at 80℃; for 16h; Product distribution / selectivity;	A 70% B n/a

(E)-1-bromo-2-iodoethylene (56798-08-4) + trimethylaluminum (75-24-1) + 1-((E,E,E)-3-methyl-1,3,5-octatrien-7-ynyl)-2,6,6-trimethyl-1-cyclohexene (111917-89-6) → beta-carotene (7235-40-7)

Conditions	Yield
Stage #1: trimethylaluminum; 1-((E,E,E)-3-methyl-1,3,5-octatrien-7-ynyl)-2,6,6-trimethyl-1-cyclohexene With zirconocene dichloride In dichloromethane at 23℃; for 4h; Stage #2: at 50℃; Stage #3: (E)-1-bromo-2-iodoethylene With tris(dibenzylideneacetone)dipalladium (0); zinc(II) chloride In tetrahydrofuran; N,N-dimethyl-formamide at 23℃; for 8h; Further stages.;	68%
Stage #1: trimethylaluminum; 1-((E,E,E)-3-methyl-1,3,5-octatrien-7-ynyl)-2,6,6-trimethyl-1-cyclohexene; zirconocene dichloride In 1,2-dichloro-ethane at 20℃; for 20h; Stage #2: (E)-1-bromo-2-iodoethylene With zinc(II) chloride; tris(dibenzylideneacetone)dipalladium (0) In tetrahydrofuran; N,N-dimethyl-formamide at 20℃; for 5h; Further stages.;	68%

C38H44ClP + (R)-9-cis-13,14-dihydro-retinal → beta-carotene (7235-40-7)

Conditions	Yield
Stage #1: C38H44ClP With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 0.5h; Stage #2: (R)-9-cis-13,14-dihydro-retinal In tetrahydrofuran; hexane at -78 - 25℃; for 1.5h;	67%

Vitamin A triphenylphosphonium sulfate → beta-carotene (7235-40-7)

Conditions	Yield
With dihydrogen peroxide; potassium carbonate In water at 15℃; for 1h;	66.1%
With bis(acetylacetonate)oxovanadium; 18-crown-6 ether; oxygen; potassium carbonate In toluene at 40℃; for 6h; Catalytic behavior; Concentration; Reagent/catalyst; Molecular sieve; Green chemistry;

C23H34OSi2 + 2-[(1’E,3’E)-3’-methyl-4’-iodobuta-1’,3’-dien-1’yl]-1,3,3-trimethylcyclohex-1-ene (138846-06-7) → beta-carotene (7235-40-7)

Conditions	Yield
Stage #1: C23H34OSi2 With potassium trimethylsilonate In tetrahydrofuran; 1,4-dioxane at 25℃; for 0.25h; Inert atmosphere; Stage #2: 2-[(1’E,3’E)-3’-methyl-4’-iodobuta-1’,3’-dien-1’yl]-1,3,3-trimethylcyclohex-1-ene With bis(dibenzylideneacetone)-palladium(0) In 1,4-dioxane at 25℃; for 1.5h; Inert atmosphere; Stage #3: C23H34OSi2 Further stages;	66%

(2E,4E,6E)-2,7-dimethyl-2,4,6-octatrienedial (5056-17-7) + (2E,4E)-3-methyl-5-(2,6,6-trimethyl-1-cyclohexenyl)-2,4-pentadien-1-ol (3917-39-3) → beta-carotene (7235-40-7)

Conditions	Yield
With tributylphosphine; phenyl isocyanate; tetrakis(triphenylphosphine) palladium(0) In acetonitrile for 5h; Heating;	65%

RETINOL (68-26-8) → beta-carotene (7235-40-7)

Conditions	Yield
Stage #1: RETINOL With pyridine In methanol Stage #2: With hydrogen bromide; triphenylphosphine In methanol at 5 - 35℃; for 35h; Reagent/catalyst; Solvent; Further stages;	64.42%
Multi-step reaction with 2 steps 1.1: hydrogenchloride / methanol; 1,4-dioxane / 2 h / 25 °C 2.1: n-butyllithium / tetrahydrofuran; hexane / 0.5 h / -78 °C 2.2: 1.5 h / -78 - 25 °C View Scheme

trans-crotonic acid butyl ester (591-63-9) + (1E,3E,5E,7E)-2-(3,7-dimethyldeca-1,3,5,7,9-pentaenyl)-1,3,3-trimethylcyclohex-1-ene → beta-carotene (7235-40-7) + butyl (2E,4E,6E,8E,10E)-5,9-dimethyl-11-(2,6,6-trimethylcyclohex-1-en-1-yl)undeca-2,4,6,8,10-pentaenoate + butyl (2E,4E,6E)-5-methyl-7-(2,6,6-trimethylcyclohex-1-en-1-yl)hepta-2,4,6-trienoate

Conditions	Yield
With Hoveyda-Grubbs catalyst second generation In toluene at 25℃; for 4.5h; Reagent/catalyst;	A 16% B 62% C 1%

aqueous sodium chloride + diethyl 3-methyl-5-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4-pentadienylphosphonate (186194-14-9) + (2E,4E,6E)-2,7-dimethyl-2,4,6-octatrienedial (5056-17-7) → beat-carotene + beta-carotene (7235-40-7)

Conditions	Yield
With potassium tert-butylate In tetrahydrofuran	A 61% B n/a

(1E,3E,5E,7E,9E)-1,10-di(benzyldimethylsilyl)-3,8-dimethyldeca-1,3,5,7,9-pentaene + 2-[(1’E,3’E)-3’-methyl-4’-iodobuta-1’,3’-dien-1’yl]-1,3,3-trimethylcyclohex-1-ene (138846-06-7) → beta-carotene (7235-40-7)

Conditions

Yield

Stage #1: (1E,3E,5E,7E,9E)-1,10-di(benzyldimethylsilyl)-3,8-dimethyldeca-1,3,5,7,9-pentaene With tetrabutyl ammonium fluoride In tetrahydrofuran at 0℃; for 0.666667h; Inert atmosphere; Stage #2: 2-[(1’E,3’E)-3’-methyl-4’-iodobuta-1’,3’-dien-1’yl]-1,3,3-trimethylcyclohex-1-ene With tris(dibenzylideneacetone)dipalladium(0) chloroform complex In tetrahydrofuran at 0 - 25℃; for 1.25h; Inert atmosphere;

61%

5,14-bis(benzenesulfonyl)-6,13-dibromo-3,7,12,16-tetramethyl-1,18-bis(2,6,6-trimethyl-1-cyclohexenyl)octadeca-1,3,9,15,17-pentaene (870636-64-9) → beta-carotene (7235-40-7) + 13-cis-β,β-carotene

Conditions	Yield
With potassium tert-butylate In cyclohexane at 80℃; for 16h;	A 60% B n/a

(1E,3E,5E,7E)-2-(3,7-dimethyldeca-1,3,5,7,9-pentaenyl)-1,3,3-trimethylcyclohex-1-ene + methyl (2E,4E)-4-methylocta-2,4,6-trienoate → beta-carotene (7235-40-7) + methyl (2E,4E,6E,8E,10E,12E,14E)-4,9,13-trimethyl-15-(2,6,6-trimethylcyclohex-1-en-1-yl)pentadeca-2,4,6,8,10,12,14-heptaenoate (69774-12-5)

Conditions	Yield
With Hoveyda-Grubbs catalyst second generation In toluene at 25℃; for 7h;	A 58% B 24%

(1E,3E,5E,7E)-2-(3,7-dimethyldeca-1,3,5,7,9-pentaenyl)-1,3,3-trimethylcyclohex-1-ene → (E)-2-(3-methylbuta-1,3-dienyl)-1,3,3-trimethyl-cyclohex-1-ene (22255-47-6) + beta-carotene (7235-40-7) + (1E,3E)-3-methyl-1-[2,6,6-trimethylcyclohex-1-enyl]hexa-1,3,5-triene (43219-55-2) + 2-((1E,3E,5E)-3,7-dimethylocta-1,3,5,7-tetraen-1-yl)-1,3,3-trimethylcyclohex-1-ene (70244-78-9, 94440-28-5)

Conditions	Yield
With tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidine][benzylidene]ruthenium(II) dichloride In dichloromethane at 50℃; for 6.5h; Inert atmosphere;	A 0.1% B 57% C 3% D 5%

C38H62P(1+)*Br(1-) → beta-carotene (7235-40-7)

Conditions	Yield
With dihydrogen peroxide; potassium hydroxide In water at 15℃; for 2h;	53.5%

beta-carotene (7235-40-7) → canthaxanthin (514-78-3)

Conditions	Yield
With cerium(IV) oxide; sulfuric acid; potassium iodide In dichloromethane; water at 0℃; under 760.051 Torr; for 2.5h; Reagent/catalyst; Temperature; UV-irradiation;	99.5%
With sulfuric acid; copper(II) sulfate; potassium iodide In dichloromethane; water at -5 - 45℃; under 760.051 Torr; for 4h; Temperature; Reagent/catalyst; Green chemistry;	98.05%
With dihydrogen peroxide; potassium iodide; lithium hydroxide In dichloromethane; water at -5 - 45℃; under 760.051 Torr; for 5.5h; Catalytic behavior; Temperature; Reagent/catalyst; Green chemistry;	98.05%

beta-carotene (7235-40-7) → all-trans-Retinal (116-31-4)

Conditions	Yield
With oxygen In water under 760.051 Torr; for 8h; Solvent; Reagent/catalyst;	89%
With osmium(VIII) oxide; diethyl ether; sodium sulfate Reagens 4: wss. H2O2;
With chloroform; dihydrogen peroxide; acetic acid
With manganese(IV) oxide

Upstream product

• 110-54-3 hexane 
• 19361-58-1 15-cis-β-carotene 
• 141-52-6 sodium ethanolate 
• 116-31-4 all-trans-Retinal 
• 68-26-8 RETINOL 
• 64-17-5 ethanol 
• 7488-99-5 alpha-carotene 
• 71-43-2 benzene 
• 5056-17-7 (2E,4E,6E)-2,7-dimethyl-2,4,6-octatrienedial 
• 3917-39-3 (2E,4E)-3-methyl-5-(2,6,6-trimethyl-1-cyclohexenyl)-2,4-pentadien-1-ol 
• 13312-52-2 9-cis-β-carotene 
• 21499-97-8 11-Dehydro-β-carotin 
• 18526-49-3 (11Z)-β,β-carotene 
• 251291-82-4 11,20-dibenzenesulfonyl-11,12,19,20-tetrahydro-β-carotene 

Downstream Products

• 25394-27-8 isocryptoxanthin 
• 122704-29-4 4-methoxy-β,β-carotene 
• 752-24-9 3,4,3',4'-tetradehydro-β,β-carotene 
• 514-78-3 canthaxanthin 
• 1923-89-3 5,6-epoxy-5,6-dihydro-β,β-carotene 
• 864-94-8 β,β-carotene diepoxide 
• 122569-69-1 (+/-)-4-ethoxy-β,β-carotene 
• 432-68-8 echinenone 
• 116-31-4 all-trans-Retinal 
• 3484-56-8 2,3,2',3',4',5'-hexadehydro-4,5'-retro-β,β-carotene 
• 1107-26-2 trans-β-apo-8'-carotenal 
• 4521-90-8 7,7'-dihydro-β-carotene 
• 13761-10-9 retro-bisdehydrocarotene 
• 991-90-2 3',4'-didehydro-β,β-caroten-4-one 

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Synthetic method for beta-carotene

The invention provides a synthetic method for beta-carotene. The synthetic method comprises the following steps: preparing an organic phosphine salt from retinol or a derivative thereof; and subjecting the organic phosphine salt to an intermolecular oxida

PRECURSOR COMPOUNDS FOR PROVIDING RETINOIDS OF THE VITAMIN A5 PATHWAY AND USES THEREOF

The invention relates to the field of retinoid X receptor (RXR) signalling and a novel vitamin A pathway called Vitamin A5 pathway. Compounds which are useful to provide (R) 9-cis-13,14-dihydro-retinoic acid an endogenous RXR ligand are claimed as well as their uses and method for preparation thereof. The compounds of the invention are useful for pharmaceutical and nutritional uses.