33016-47-6

Basic information

• Product Name: 1-Tritylimidazole-4-carboxaldehyde
• Synonyms: 1-(TRIPHENYLMETHYL)IMIDAZOLE-4-CARBOXALDEHYDE;1-TRITYL-1H-IMIDAZOLE-4-CARBOXALDEHYDE;1-TRITYLIMIDAZOLE-4-CARBOXALDEHYDE;4-FORMYL-1-TRITYLIMIDAZOLE;AKOS 215-50;RARECHEM AN KA 0027;1-TRITYL-IMDAZOLE-4-CARBOXADEHYDE;1-Trityl-1H-imidazole-4-carboxaldehyde 98%
• CAS NO: 33016-47-6
• Molecular Formula: C₂₃H₁₈N₂O
• Molecular Weight: 338.4
• EINECS: 1312995-182-4
• Product Categories: Aldehydes;blocks;Imidazoles;Heterocyclic Building Blocks
• Mol File: 33016-47-6.mol
• Article Data: 58

Chemical Properties

• Melting Point: 180-190°C
• Boiling Point: 502.8 °C at 760 mmHg
• Flash Point: 257.9 °C
• Appearance: White to brown/Crystalline Powder
• Density: 1.1 g/cm³
• Vapor Pressure: 3.06E-10mmHg at 25°C
• Refractive Index: 1.612
• Storage Temp.: under inert gas (nitrogen or Argon) at 2-8°C
• Solubility: Acetonitrile (Slightly), Methanol (Slightly)
• PKA: 2.28±0.61(Predicted)
• CAS DataBase Reference: 1-Tritylimidazole-4-carboxaldehyde(CAS DataBase Reference)
• NIST Chemistry Reference: 1-Tritylimidazole-4-carboxaldehyde(33016-47-6)
• EPA Substance Registry System: 1-Tritylimidazole-4-carboxaldehyde(33016-47-6)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36/37/39-37
• Hazardous Substances Data: 33016-47-6(Hazardous Substances Data)

Usage

Uses

1-Tritylimidazole-4-carboxaldehyde is used in the synthesis of histamine and girolline

InChI:InChI=1/C23H18N2O/c26-17-22-16-25(18-24-22)23(19-10-4-1-5-11-19,20-12-6-2-7-13-20)21-14-8-3-9-15-21/h1-18H

Synthetic route

trityl chloride (76-83-5) + 4(5)formylimidazole (3034-50-2) → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
With triethylamine In dichloromethane at 20℃;	100%
With triethylamine In N,N-dimethyl-formamide at 0 - 20℃;	100%
With triethylamine In N,N-dimethyl-formamide at 20℃;	99%

5-imidazolecarboxaldehyde (3034-50-2) + trityl chloride (76-83-5) → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
In dichloromethane at 0 - 20℃;	98%
With triethylamine In acetonitrile at 20℃;	94%
With triethylamine In acetonitrile at 20℃; for 20.3333h;	94%

4-(hydroxymethyl)-1-(triphenylmethyl)imidazole (33769-07-2) → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
With manganese(IV) oxide In 1,4-dioxane for 5h; Heating;	95%
With oxalyl dichloride; dimethyl sulfoxide In dichloromethane at -70℃; for 0.333333h;	82%
With Mn2O In 1,4-dioxane at 85℃; for 6h;	80%

N-trityl-4(5)-iodoimidazole (96797-15-8) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → 1-tritylimidazole-2,4-dicarboxaldehyde (96797-16-9) + 1-(triphenylmethyl)-1H-imidazole-2-carboxaldehyde (67478-50-6) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
With n-butyllithium In tetrahydrofuran; hexane Product distribution; cooling in a dry ice acetone bath, excess n-BuLi;	A 8 mg B 11% C 83%
With n-butyllithium 1.) THF, hexane, 5 s, cooling in a dry ice acetone bath; Yield given. Multistep reaction. Yields of byproduct given;

N-trityl-4(5)-iodoimidazole (96797-15-8) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
Stage #1: N-trityl-4(5)-iodoimidazole With ethylmagnesium bromide In diethyl ether; dichloromethane at 20℃; for 0.5h; Stage #2: N,N-dimethyl-formamide In diethyl ether; dichloromethane at 20℃; for 0.5h;	82%
Stage #1: N-trityl-4(5)-iodoimidazole With ethylmagnesium bromide In dichloromethane Stage #2: N,N-dimethyl-formamide In dichloromethane at 20℃;	82%
Stage #1: N-trityl-4(5)-iodoimidazole With isopropylmagnesium chloride In dichloromethane at 10 - 20℃; Stage #2: N,N-dimethyl-formamide In dichloromethane at -5 - 20℃; for 10.5h; Stage #3: With water; ammonium chloride In dichloromethane at 20℃;	73.2%

N-trityl-4(5)-iodoimidazole (96797-15-8) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → N-tritylimidazole (15469-97-3) + 4-iodo-2-formyl-1-tritylimidazole + 1-(triphenylmethyl)-1H-imidazole-2-carboxaldehyde (67478-50-6) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
With n-butyllithium In tetrahydrofuran; hexane Product distribution; cooling in a dry ice acetone bath, stoichiometric n-BuLi;	A 19% B 16% C 7% D 51%
With n-butyllithium 1.) THF, hexane, 5 s, cooling in a dry ice acetone bath; Yield given. Multistep reaction. Yields of byproduct given;

N-Formylpiperidine (2591-86-8) + N-trityl-4(5)-iodoimidazole (96797-15-8) → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
With ethylmagnesium bromide 1.) THF, Et2O, room temp., 30 min., 2.) 1 h; Yield given. Multistep reaction;

trityl chloride (76-83-5) + amalgamated silver → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: 94 percent / TEA / dimethylformamide View Scheme

trityl chloride (76-83-5) + Me-X → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: imidazole / dimethylformamide 2: MnO2 / dioxane View Scheme

trityl chloride (76-83-5) + DL-lysine methyl ester dihydrochloride → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: 93 percent / Et3N / dimethylformamide / 18 h 2: 80 percent / Mn2O / dioxane / 6 h / 85 °C View Scheme

trityl chloride (76-83-5) → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: Et3N / dimethylformamide 2: MnO2 / dioxane View Scheme
With triethylamine In dichloromethane; water
With triethylamine In N,N-dimethyl-formamide; benzene

1-trityl-1H-imidazole-4-carboxaldehyde resin → (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6)

Conditions	Yield
With trifluoroacetic acid In dichloromethane trityl chloride resin;

(1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) + 1-(5-fluoro-3-methylbenzo[b]thiophen-2-yl)ethanone (51828-34-3) → (E)-1-(5-fluoro-3-methylbenzo[b]thiophen-2-yl)-3-(1-triphenylmethyl-1H-imidazol-4-yl)-2-propen-1-one (212078-55-2)

Conditions	Yield
With sodium hydroxide In tetrahydrofuran; methanol at 20℃; for 4h; Claisen-Schmidt reaction;	100%

Nitroethane (79-24-3) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 4-(2-nitro-propenyl)-1-trityl-1H-imidazole

Conditions	Yield
With ammonium acetate for 6h; Henry reaction; Reflux;	100%

ammonium chloride + 2-oxopiperidine-1-carboxylic acid tert-butyl ester (85908-96-9) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → tert-Butyl 3-[hydroxy(1-trityl-1H-imidazol-4-yl)methyl]-2-oxo-1-piperidinecarboxylate

Conditions	Yield
With lithium diisopropyl amide In tetrahydrofuran; cyclohexane	99%

2-aminoethylpyridine (42088-91-5) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 1-(pyridin-2-yl)-N-((1-trityl-1H-imidazol-4-yl)methylene)ethanamine

Conditions	Yield
In ethanol at 0 - 20℃;	99%

(1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 4(5)formylimidazole (3034-50-2)

Conditions	Yield
With acetic acid In methanol for 7h; Heating;	98%
With acetic acid In methanol for 13h; Heating;	82%

methylmagnesium bromide (75-16-1) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → alpha-methyl-1-triphenylmethyl-1H-imidazole-4-methanol (62256-50-2)

Conditions	Yield
In tetrahydrofuran; diethyl ether for 1h; Grignard reaction;	98%
Stage #1: methylmagnesium bromide; (1-tritylimidazol-4-yl)carboxaldehyde In tetrahydrofuran; hexane at 0 - 20℃; Stage #2: With water; ammonium chloride In tetrahydrofuran; hexane	75%
In tetrahydrofuran; diethyl ether at 20℃; for 1.5h;
Stage #1: methylmagnesium bromide; (1-tritylimidazol-4-yl)carboxaldehyde In tetrahydrofuran; diethyl ether at 15℃; for 4h; Stage #2: With water; ammonium chloride In tetrahydrofuran; diethyl ether

benzylamine (100-46-9) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → C30H27N3 (186422-32-2)

Conditions	Yield
Stage #1: benzylamine; (1-tritylimidazol-4-yl)carboxaldehyde With sodium acetate In methanol at 20℃; Stage #2: With sodium tetrahydroborate for 4h;	98%
With sodium tetrahydroborate; sodium acetate In methanol at 20℃; 3°A molecular sieves;	98%
With sodium tris(acetoxy)borohydride In dichloromethane at 20℃;

3-[2-(aminomethyl)-5-chlorophenyl]propanoic acid hydrochloride (1076192-18-1) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 3-[5-chloro-2-({[(1-trityl-1H-imidazol-4-yl)methyl]amino}methyl)phenyl]propanoic acid (1076192-20-5)

Conditions	Yield
Stage #1: 3-[2-(aminomethyl)-5-chlorophenyl]propanoic acid hydrochloride; (1-tritylimidazol-4-yl)carboxaldehyde With triethylamine; trimethyl orthoformate In methanol at 20℃; for 16h; Stage #2: With sodium tetrahydroborate In methanol for 1h; Stage #3: With sodium hydrogencarbonate In methanol; water pH=5 - 6;	96%

diethoxyphosphoryl-acetic acid ethyl ester (867-13-0) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → (E)-3-(1-triphenylmethyl-1H-imidazol-4-yl)-2-propenoic acid ethyl ester (111157-50-7)

Conditions	Yield
With potassium hydroxide In tetrahydrofuran Ambient temperature;	95%

vinyl magnesium bromide (1826-67-1) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 1-(1-trityl-1H-imidazol-4-yl)-prop-2-en-1-ol (127798-61-2)

Conditions	Yield
In tetrahydrofuran for 12h; Ambient temperature;	94%
In tetrahydrofuran at -10℃;	87%
In tetrahydrofuran Grignard reaction;	41%

phenylmagnesium bromide (100-58-3) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 1-triphenylmethyl-4-[(1-hydroxy-1-phenyl)methyl]-1H-imidazole (135773-27-2)

Conditions	Yield
With manganese dioxide In tetrahydrofuran; 1,4-dioxane	94%

(1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) + methyl trifluoromethanesulfonate (333-27-7) → 3-methyl-3H-imidazole-4-carboxaldehyde trifluoromethanesulfonate

Conditions	Yield
In dichloromethane at 20℃;	93%

diethyl (cyanomethyl)phosphonate + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 1-trityl-4-(2-cyanoethyl)imidazole (154312-79-5)

Conditions	Yield
With sodium amide In tetrahydrofuran 1.) room temperature, 1 h, 2.) reflux, 20 h;	92%

2-(1,3-dioxoisoindolin-2-yl)ethyltriphenylphosphonium bromide (65273-64-5) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → (E)-N-[3-(1-Triphenylmethyl-1H-imidazol-4-yl)allyl]phthalimid (112547-04-3)

Conditions	Yield
With potassium tert-butylate In tetrahydrofuran at 0 - 60℃; for 3h;	92%

[3-(1,3-dioxo-1,3-dihydro-isoindol-2-yl)-propyl]-triphenyl-phosphonium bromide (7743-29-5) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 2-[(E)-4-(1-Trityl-1H-imidazol-4-yl)-but-3-enyl]-isoindole-1,3-dione

Conditions	Yield
With potassium tert-butylate In tetrahydrofuran at 0 - 60℃; for 3h;	92%

(4-phthalimidobutyl)triphenylphosphonium bromide (65273-47-4) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 2-[(E)-5-(1-Trityl-1H-imidazol-4-yl)-pent-4-enyl]-isoindole-1,3-dione

Conditions	Yield
With potassium tert-butylate In tetrahydrofuran at 0 - 60℃; for 3h;	92%

diethyl 1-cyanomethylphosphonate (2537-48-6) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 1-trityl-4-(2-cyanoethyl)imidazole (154312-79-5)

Conditions	Yield
Stage #1: (1-tritylimidazol-4-yl)carboxaldehyde With sodium amide In tetrahydrofuran Stage #2: diethyl 1-cyanomethylphosphonate In tetrahydrofuran at 20℃;	92%
With sodium amide In tetrahydrofuran Heating;

ethyl bromozincacetate;THF + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → ethyl 3-hydroxy-3-(1-trityl-1H-imidazol-4-yl)propanoate (426219-40-1)

Conditions	Yield
Stage #1: 1-triphenylmethyl-5-imidazolecarboxaldehyde; ethyl bromozincacetate;THF In tetrahydrofuran at 0 - 6℃; for 1.41667h; Stage #2: ethyl bromozincacetate;THF In tetrahydrofuran at 0 - 3℃; for 5.5h; Stage #3: With hydrogenchloride In tetrahydrofuran; water at 20℃;	92%

2,3-dimethylbromobenzene (576-23-8) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 4-<(2,3-dimethylphenyl)hydroxymethyl>-1-(triphenylmethyl)imidazole (176721-01-0)

Conditions	Yield
Stage #1: 2,3-dimethylbromobenzene With iodine; magnesium In tetrahydrofuran at 70℃; for 1.5h; Inert atmosphere; Stage #2: (1-tritylimidazol-4-yl)carboxaldehyde In tetrahydrofuran at -5 - 20℃; Inert atmosphere;	91.1%
Stage #1: 2,3-dimethylbromobenzene With iodine; magnesium In tetrahydrofuran for 1h; Reflux; Stage #2: (1-tritylimidazol-4-yl)carboxaldehyde In tetrahydrofuran at 0 - 20℃; for 1.5h;	53.9%
With iodine; magnesium 1.) THF, reflux, 1 h, 2.) r.t., THF, 1.5 h; Yield given. Multistep reaction;
Stage #1: 2,3-dimethylbromobenzene With magnesium In tetrahydrofuran Stage #2: (1-tritylimidazol-4-yl)carboxaldehyde In tetrahydrofuran at 0℃;

nitromethane (75-52-5) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 4-(E)-(2-nitroethenyl)-1-(triphenylmethyl)-1H-imidazole (139285-03-3)

Conditions	Yield
With piperidine; acetic acid Ambient temperature;	91%
With piperidine; acetic acid at 20℃; for 10h;	82%
With piperidine; acetic acid at 20℃; for 8h;	79%
With ammonium acetate In acetic acid at 22℃; for 6h; Knovenagel condensation; sonication;	52%
With piperidine; acetic acid at 20℃; for 18h;

sodium chlorite (7758-19-2) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 1H-1-triphenylmethylimidazole-4-carboxylic acid (191103-80-7)

Conditions	Yield
With potassium dihydrogenphosphate In water	91%

4-amino-1-benzylpiperidine (50541-93-0) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 1-benzyl-N-[(1-trityl-1H-imidazol-4-yl)methyl]piperidin-4-amine (701300-00-7)

Conditions	Yield
Stage #1: 4-amino-1-benzylpiperidine; (1-tritylimidazol-4-yl)carboxaldehyde With sodium tris(acetoxy)borohydride; acetic acid In dichloromethane at 20℃; Stage #2: With sodium hydroxide In dichloromethane	90%

3,4-dimethyliodobenzene (31599-61-8) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → C31H28N2O

Conditions	Yield
Stage #1: 3,4-dimethyliodobenzene With isopropylmagnesium chloride In tetrahydrofuran at 12 - 15℃; for 3.33h; Stage #2: (1-tritylimidazol-4-yl)carboxaldehyde In tetrahydrofuran at 15 - 25℃; for 3h;	89.9%

trimethyl 2-(tert-butoxycarbonylamino)phosphonoacetate (121056-95-9) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 2-tert-butoxycarbonylamino-3-(1-trityl-1H-imidazol-4-yl)acrylic acid methyl ester

Conditions	Yield
With 1,8-diazabicyclo[5.4.0]undec-7-ene at 20℃; Horner-Wadsworth-Emmons reaction;	89%
With N,N,N',N'-tetramethylguanidine In tetrahydrofuran at 0 - 20℃; for 21h;

Methyltriphenylphosphonium bromide (1779-49-3) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → 4-ethenyl-1-(triphenylmethyl)-1H-imidazole (86803-29-4)

Conditions	Yield
Stage #1: Methyltriphenylphosphonium bromide With sodium hexamethyldisilazane In tetrahydrofuran at 0℃; for 0.5h; Stage #2: (1-tritylimidazol-4-yl)carboxaldehyde In tetrahydrofuran at 0 - 20℃; for 3h;	86%
With sodium hydride In dimethyl sulfoxide at 70℃; for 4.5h;	82%
With sodium hydride In tetrahydrofuran for 8h; Ambient temperature;	81%
Stage #1: Methyltriphenylphosphonium bromide With potassium tert-butylate In tetrahydrofuran for 0.5h; Inert atmosphere; Stage #2: (1-tritylimidazol-4-yl)carboxaldehyde In tetrahydrofuran at 20℃; for 2h; Wittig Olefination; Inert atmosphere;	66%

(2-tert-butoxy-2-oxoethyl)zinc(II) bromide (51656-70-3) + (1-tritylimidazol-4-yl)carboxaldehyde (33016-47-6) → tert-butyl 3-hydroxy-3-(1-trityl-1H-imidazol-4-yl)propanoate

Conditions	Yield
Stage #1: 1-triphenylmethyl-5-imidazolecarboxaldehyde; tert-butyl bromozincacetate In tetrahydrofuran at 2 - 9℃; for 3.5h; Stage #2: With hydrogenchloride In tetrahydrofuran; water at 20℃;	86%

Upstream product

• 76-83-5 trityl chloride 
• 3034-50-2 4⁽⁵⁾formylimidazole 
• 3034-50-2 5-imidazolecarboxaldehyde 
• 96797-15-8 N-trityl-4⁽⁵⁾-iodoimidazole 
• 68-12-2 N,N-dimethyl-formamide 
• 2591-86-8 N-Formylpiperidine 
• 33769-07-2 4-(hydroxymethyl)-1-(triphenylmethyl)imidazole 

Downstream Products

• 146197-52-6 4-(α-hydroxy-3-methoxymethoxymethyl-2-methylbenzyl)-1-triphenylmethylimidazole 
• 252259-66-8 (S)-1-(1-triphenylmethylimidazol-4-ylmethyl)-2-(2-methoxyethyl)-4-(1-naphthalenylcarbonyl)piperazine 
• 85103-02-2 1-(4-nitrobenzyl)-1H-imidazole-5-carbaldehyde 
• 406225-21-6 (Z)-4-(3-(1,3-dioxolan-2-yl)prop-1-enyl)-1-trityl-1H-imidazole 
• 154312-79-5 1-trityl-4-(2-cyanoethyl)imidazole 
• 62256-50-2 alpha-methyl-1-triphenylmethyl-1H-imidazole-4-methanol 
• 176721-02-1 4-<(2,3-dimethylphenyl)carbonyl>-1-(triphenylmethyl)imidazole 
• 176721-03-2 4-<1-(2,3-dimethylphenyl)-1-hydroxyethyl>-1-(triphenylmethyl)imidazole 
• 127798-62-3 4-[1-(tert-Butyl-dimethyl-silanyloxy)-allyl]-1-trityl-1H-imidazole 
• 127798-63-4 [3-(tert-Butyl-dimethyl-silanyloxy)-2-hydroxy-3-(1-trityl-1H-imidazol-4-yl)-propyl]-carbamic acid tert-butyl ester 
• 127798-63-4 [3-(tert-Butyl-dimethyl-silanyloxy)-2-hydroxy-3-(1-trityl-1H-imidazol-4-yl)-propyl]-carbamic acid tert-butyl ester 
• 127798-66-7 [3-(tert-Butyl-dimethyl-silanyloxy)-2-chloro-3-(1-trityl-1H-imidazol-4-yl)-propyl]-carbamic acid tert-butyl ester 
• 127798-66-7 [3-(tert-Butyl-dimethyl-silanyloxy)-2-chloro-3-(1-trityl-1H-imidazol-4-yl)-propyl]-carbamic acid tert-butyl ester 
• 127798-64-5 Acetic acid 1-(tert-butoxycarbonylamino-methyl)-2-(tert-butyl-dimethyl-silanyloxy)-2-(1-trityl-1H-imidazol-4-yl)-ethyl ester 

Relevant articles and documents

Efficient molar-scale synthesis of 1-methyl-5-acylimidazole triflic acid salts

A new process for the molar-scale preparation of 1-methyl-5-acylimidazole triflic acid salts was developed. The new process consists of: (i) regioselective 3N-tritylation of 5-acylimidazole to give 3-trityl-5-acylimidazoles, (ii) 1N-methylation of 3-trityl-5-acylimidazoles, and (iii) hydrolysis of the resulting quaternary ammonium salts to afford 1-methyl-5-acylimidazole triflic acid salts. This process is highly efficient, affording 1-methyl-5-acylimidazole triflic acid salts in 86-88% overall yield in three steps without chromatographic separation of products.

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PURIFIED CRYSTALLINE DETOMIDINE HYDROCHLORIDE MONOHYDRATE, ANHYDRATE AND FREE BASE WITH LOW AMOUNTS OF ISO-DETOMIDINE AND OTHER IMPURITIES BY RECRYSTALLISATION IN WATER

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