941-37-7

Basic information

• Product Name: 1-Bromo-3,5-dimethyladamantane
• Synonyms: 1-Bromo-3,5-dimethyltricyclo[3.3.1.13,7]decane;1-BROMO-3,5-DIMETHYLADAMANTANE;3,5-dimethyl-1-bromo- adamantane;1-Bromo-3,5-Dimethyl;1-BROMO-3,5- DIMETHYL DAMANTANE;1,3-Dimethyl-5-bromoadamantane;tricyclo[3.3.1.1~3,7~]decane, 1-bromo-3,5-dimethyl-;NSC 102293
• CAS NO: 941-37-7
• Molecular Formula: C₁₂H₁₉Br
• Molecular Weight: 243.18
• EINECS: 213-378-9
• Product Categories: Chemical intermediate for Memantine HCl;Adamantane derivatives;Adamantanes;Alkyl;Halogenated Hydrocarbons;Organic Building Blocks;Intermediates & Fine Chemicals;Pharmaceuticals
• Mol File: 941-37-7.mol

Chemical Properties

• Boiling Point: 201 °C(lit.)
• Flash Point: 228 °F
• Appearance: clear colorless oil
• Density: 1.224 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.0385mmHg at 25°C
• Refractive Index: n20/D 1.52(lit.)
• Storage Temp.: Refrigerator
• Solubility: Chloroform (Sparingly), Dichloromethane (Slightly), Methanol (Slightly)
• BRN: 1927514
• CAS DataBase Reference: 1-Bromo-3,5-dimethyladamantane(CAS DataBase Reference)
• NIST Chemistry Reference: 1-Bromo-3,5-dimethyladamantane(941-37-7)
• EPA Substance Registry System: 1-Bromo-3,5-dimethyladamantane(941-37-7)

Safety Data

• Hazard Codes: C
• Statements: 34-36
• Safety Statements: 26-27-36/37/39-45
• WGK Germany: 3
• HazardClass: IRRITANT
• Hazardous Substances Data: 941-37-7(Hazardous Substances Data)

Usage

Uses

Used in Organic Synthesis:
1-Bromo-3,5-dimethyladamantane is used as a synthetic intermediate for the preparation of various organic compounds. Its unique adamantane framework and bromo substituent make it a valuable building block in the synthesis of complex organic molecules and pharmaceuticals.
Used in the Synthesis of 1,3-Dicarbonyl Adamantanes:
1-Bromo-3,5-dimethyladamantane is used as a starting material in the one-pot synthesis of 1,3-dicarbonyl adamantanes. These compounds are of interest due to their potential applications in various fields, such as pharmaceuticals and materials science.
Used in the Synthesis of 3,5-Dimethyladamantan-1-ol:
1-Bromo-3,5-dimethyladamantane is also utilized in the synthesis of 3,5-dimethyladamantan-1-ol, which is an important intermediate for the production of various chemical compounds and may have potential applications in the fragrance and flavor industries.

InChI:InChI=1/C12H19Br/c1-10-3-9-4-11(2,6-10)8-12(13,5-9)7-10/h9H,3-8H2,1-2H3

Synthetic route

1,3-dimethyladamantane (702-79-4) → 3,5-dimethyl-1-bromoadamantane (941-37-7)

Conditions	Yield
With aluminum (III) chloride; bromine In 1,2-dichloro-ethane at 15℃; Reagent/catalyst; Temperature; Solvent;	92%
With bromine for 12h; Reflux;	91.5%
With iron(III)-acetylacetonate; carbon tetrabromide at 150℃; for 3h; Sealed tube; Inert atmosphere;	85%

1-acetamido-3,5-dimethyladamantane (19982-07-1) → 1,3-dimethyl-5-adamantanol (707-37-9) + 3,5-dimethyl-1-bromoadamantane (941-37-7) + memantine* (19982-08-2) + memantine hydrochloride (41100-52-1)

Conditions	Yield
Stage #1: 1-acetamido-3,5-dimethyladamantane With sodium hydroxide In diethylene glycol at 105 - 170℃; for 10h; Stage #2: With hydrogenchloride In water; toluene at 5 - 15℃; for 2.5h; Product distribution / selectivity;

1,3-dimethyl-5-adamantanol (707-37-9) → 3,5-dimethyl-1-bromoadamantane (941-37-7)

Conditions	Yield
With hydrogen bromide In water for 0.666667h; Inert atmosphere;

1,3-dimethyladamantane (702-79-4) → 1,3-dimethyl-5-adamantanol (707-37-9) + 3,5-dimethyl-1-bromoadamantane (941-37-7) + 2-bromo-3,5-dimethyladamantane

Conditions	Yield
With pyridine; carbon tetrabromide; water; manganese(III) acetylacetonate Catalytic behavior; Concentration; Temperature; Time; Heating;

3,5-dimethyl-1-bromoadamantane (941-37-7) → 1,3-dimethyladamantane (702-79-4)

Conditions	Yield
With 2,2'-azobis(isobutyronitrile); tri-n-butyl-tin hydride at 90℃; for 1h; Solvent; Barton-McCombie Deoxygenation; Inert atmosphere;	100%
With decane; 2,2’-azobis(4-methoxy-2,4-dimethyl)valeronitrile; tri-n-butyl-tin hydride In toluene at 80℃; for 0.0166667h;	99 % Chromat.
Multi-step reaction with 2 steps 1: 98 percent / aq. HCl / dimethylformamide / 1.5 h 2: H2SO4 (91.5percent) / 72 h / Ambient temperature; var. of conc.of H2SO4, and var. of reaction time View Scheme

acetamide (60-35-5) + 3,5-dimethyl-1-bromoadamantane (941-37-7) → 1-acetamido-3,5-dimethyladamantane (19982-07-1)

Conditions	Yield
With dimanganese decacarbonyl at 120 - 130℃; Inert atmosphere; Autoclave;	99%
at 125℃; Temperature;	94%
at 70 - 160℃; for 6h; Temperature; Inert atmosphere;	92.4%

3,5-dimethyl-1-bromoadamantane (941-37-7) → 1,3-dimethyl-5-adamantanol (707-37-9)

Conditions	Yield
With hydrogenchloride In N,N-dimethyl-formamide for 1.5h;	98%
With sodium hydroxide In ethanol at 70℃; Temperature;	85%
With potassium carbonate at 150℃; for 6h;
With sodium hydroxide In water for 4h; Reflux;

3,5-dimethyl-1-bromoadamantane (941-37-7) + methylmagnesium bromide (75-16-1) → 1,3-dimethyladamantane (702-79-4) + 1,3,5-trimethyladamantane (707-35-7)

Conditions	Yield
In dibutyl ether at 95℃;	A 2% B 98%

3,5-dimethyl-1-bromoadamantane (941-37-7) + Propionamid (79-05-0) → N-(3,5-dimethyladamant-1-yl)propanamide

Conditions	Yield
With dimanganese decacarbonyl at 120 - 130℃; Inert atmosphere; Autoclave;	98%

3,5-dimethyl-1-bromoadamantane (941-37-7) + benzamide (55-21-0) → N-(3,5-dimethyladamant-1-yl)benzamide

Conditions	Yield
With dimanganese decacarbonyl at 120 - 130℃; Inert atmosphere; Autoclave;	97%

3,5-dimethyl-1-bromoadamantane (941-37-7) + urea (57-13-6) → memantine hydrochloride (41100-52-1)

Conditions	Yield
Stage #1: 3,5-dimethyl-1-bromoadamantane; urea In 1-methyl-pyrrolidin-2-one at 120℃; for 4h; Stage #2: With sodium hydroxide In 1-methyl-pyrrolidin-2-one at 120℃; for 6h; Stage #3: With hydrogenchloride In 1-methyl-pyrrolidin-2-one; water at 25℃; for 16h; Solvent; Temperature;	97%

3,5-dimethyl-1-bromoadamantane (941-37-7) + acetonitrile (75-05-8) → 1-acetamido-3,5-dimethyladamantane (19982-07-1)

Conditions	Yield
With sulfuric acid for 12h;	96%
Stage #1: 3,5-dimethyl-1-bromoadamantane; acetonitrile With phosphoric acid at 20 - 87℃; for 3.75 - 4.33h; Stage #2: With sodium hydroxide; water; butan-1-ol at 35 - 45℃; pH=5.5 - 7;	95.5%
With sulfuric acid at 20℃;	80%

3,5-dimethyl-1-bromoadamantane (941-37-7) + methylmagnesium bromide (75-16-1) → 1,3,5-trimethyladamantane (707-35-7)

Conditions	Yield
In dibutyl ether at 116℃;	95%

Isopropenyl acetate (108-22-5) + 3,5-dimethyl-1-bromoadamantane (941-37-7) → 1-(3,5-dimethyladamantan-1-yl)propan-2-one

Conditions	Yield
Stage #1: 3,5-dimethyl-1-bromoadamantane With aluminum tri-bromide In dichloromethane at -10℃; for 0.5h; Stage #2: Isopropenyl acetate In dichloromethane at -10℃; for 0.5h;	91%

3,5-dimethyl-1-bromoadamantane (941-37-7) → memantine* (19982-08-2)

Conditions	Yield
Stage #1: 3,5-dimethyl-1-bromoadamantane With ammonium acetate In N,N-dimethyl-formamide at 150℃; for 5.5h; Stage #2: With hydrogenchloride In water; N,N-dimethyl-formamide at 5℃; for 0.5h;	90%
Stage #1: 3,5-dimethyl-1-bromoadamantane With acetamide at 130℃; for 5h; Stage #2: With sodium hydroxide In ethylene glycol at 200℃; for 7h;	75%
Multi-step reaction with 2 steps 1: H2SO4 2: KOH View Scheme

2-phenyl-1,2,3,4-tetrahydroisoquinoline (3340-78-1) + 3,5-dimethyl-1-bromoadamantane (941-37-7) → 1-(3,5-dimethyladamantan-1-yl)-2-phenyl-1,2,3,4-tetrahydroisoquinoline

Conditions	Yield
With 2,4,6-trimethyl-pyridine; tetrakis(triphenylphosphine) palladium(0) In N,N-dimethyl-formamide at 20℃; for 16h; Inert atmosphere; Schlenk technique; Irradiation;	90%

3,5-dimethyl-1-bromoadamantane (941-37-7) → memantine hydrochloride (41100-52-1)

Conditions	Yield
Stage #1: 3,5-dimethyl-1-bromoadamantane With sulfuric acid; toluene-4-sulfonic acid; acetonitrile at 30 - 50℃; for 2h; Stage #2: With hydrogenchloride In water; ethyl acetate for 2h; Reagent/catalyst;	88.44%
Stage #1: 3,5-dimethyl-1-bromoadamantane With formic acid; urethane at 20 - 90℃; for 1h; Inert atmosphere; Stage #2: With hydrogenchloride In water at 20 - 110℃; for 4h; Reagent/catalyst; Temperature; Inert atmosphere;	85%
Multi-step reaction with 3 steps 1: sulfuric acid / 12 h 2: sodium hydroxide / water; ethylene glycol / 12 h / 150 °C 3: hydrogenchloride / pH 6 / Gas phase View Scheme

carbon monoxide (201230-82-2) + 3,5-dimethyl-1-bromoadamantane (941-37-7) + aniline (62-53-3) → 1,3-Me2-5,7-Ad(CONHC6H5)2 (1344030-14-3)

Conditions	Yield
Stage #1: carbon monoxide; 3,5-dimethyl-1-bromoadamantane With aluminum tri-bromide; carbon tetrabromide In methylene dibromide at 0 - 20℃; under 760.051 Torr; for 3h; Stage #2: aniline In methylene dibromide at 0℃;	88%

1,1'-azobis (cyclohexanecarbonitrile) (2094-98-6) + 3,5-dimethyl-1-bromoadamantane (941-37-7) + tri-n-butyl-tin hydride (688-73-3) + acrylonitrile (107-13-1) → 3-(3, 5-Dimethyl-1-adamantyl)propionitrile (227323-46-8)

Conditions	Yield
In toluene	86%

carbon dioxide (124-38-9) + 3,5-dimethyl-1-bromoadamantane (941-37-7) + N-benzyl-2-phenyl-1-prop-2-enamine (123974-18-5) → 3-benzyl-5-((3,5-dimethyladamantan-1-yl)methyl)-5-phenyloxazolidin-2-one

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine In dimethyl sulfoxide under 760.051 Torr; for 24h; Schlenk technique; Irradiation; Sealed tube;	86%

3,5-dimethyl-1-bromoadamantane (941-37-7) → 1-azido-3,5-dimethyladamantane (63534-29-2)

Conditions	Yield
With trimethylsilylazide; tin(IV) chloride In dichloromethane at 50℃; for 10h; Inert atmosphere;	85%
With trimethylsilylazide; tin(IV) chloride In dichloromethane for 12h; Ambient temperature;	71%

morpholine (110-91-8) + carbon monoxide (201230-82-2) + 3,5-dimethyl-1-bromoadamantane (941-37-7) → C22H34N2O4 (1344030-15-4)

Conditions	Yield
Stage #1: carbon monoxide; 3,5-dimethyl-1-bromoadamantane With aluminum tri-bromide; carbon tetrabromide In methylene dibromide at 0 - 20℃; under 760.051 Torr; for 3h; Stage #2: morpholine In methylene dibromide at 0℃;	85%

3,5-dimethyl-1-bromoadamantane (941-37-7) → (3,5-dimethyladamantyl)phosphonic acid dichloride (125282-04-4)

Conditions	Yield
With sulfuric acid; phosphorus trichloride at 20 - 50℃; for 2h;	82%

carbon monoxide (201230-82-2) + 3,5-dimethyl-1-bromoadamantane (941-37-7) → (3,5-dimethyl-adamantan-1-yl)-methanol (26919-42-6)

Conditions	Yield
With 2,2'-azobis(isobutyronitrile); α,α,α-trifluorotoluene; (C6F13CH2CH2)3SnH; sodium cyanoborohydride In tert-butyl alcohol at 90℃; under 60800 Torr; for 3h;	79%

carbon monoxide (201230-82-2) + 3,5-dimethyl-1-bromoadamantane (941-37-7) + isopropyl alcohol (67-63-0) → 1.3-Me2-5,7-Ad(COOiPr)2 (1344030-12-1)

Conditions	Yield
Stage #1: carbon monoxide; 3,5-dimethyl-1-bromoadamantane With aluminum tri-bromide; carbon tetrabromide In methylene dibromide at 0 - 20℃; under 760.051 Torr; for 3h; Stage #2: isopropyl alcohol In methylene dibromide at 0℃;	79%

3,5-dimethyl-1-bromoadamantane (941-37-7) + potassium phtalimide (1074-82-4) → 2-(3,5-dimethyladamantan-1-yl)isoindoline-1,3-dione (1204184-74-6)

Conditions	Yield
In N,N-dimethyl-formamide at 25 - 130℃;	78.64%

3,5-dimethyl-1-bromoadamantane (941-37-7) + formamide (77287-34-4, 77287-35-5, 60100-09-6) → 1-formamido-3,5-dimethyltricyclo[3.3.1.13,7]decane (351329-88-9)

Conditions	Yield
With dimanganese decacarbonyl at 120 - 130℃; Inert atmosphere; Autoclave;	78%
at 22 - 75℃; Product distribution / selectivity; Inert atmosphere;
Stage #1: 3,5-dimethyl-1-bromoadamantane; formamide at 120℃; Stage #2: With sodium hydroxide In dichloromethane
at 150℃; for 8h;
at 140℃; for 12h; Temperature;

carbon monoxide (201230-82-2) + 3,5-dimethyl-1-bromoadamantane (941-37-7) + diethylamine (109-89-7) → 1,3-Me2-5,7-Ad(CONEt2)2 (1344030-13-2)

Conditions	Yield
Stage #1: carbon monoxide; 3,5-dimethyl-1-bromoadamantane With aluminum tri-bromide; carbon tetrabromide In methylene dibromide at 0 - 20℃; under 760.051 Torr; for 3h; Stage #2: diethylamine In methylene dibromide at 0℃;	75%

carbon monoxide (201230-82-2) + 3,5-dimethyl-1-bromoadamantane (941-37-7) + methoxybenzene (100-66-3) → 1,3-Me2-5,7-Ad(COC6H4OMe)2

Conditions	Yield
Stage #1: carbon monoxide; 3,5-dimethyl-1-bromoadamantane With aluminum tri-bromide; carbon tetrabromide In methylene dibromide at 0 - 20℃; under 760.051 Torr; for 3h; Stage #2: methoxybenzene In methylene dibromide at 0℃;	73%

N,N'-Dimethylurea (96-31-1) + 3,5-dimethyl-1-bromoadamantane (941-37-7) → 1-N-methylamino-3,5-dimethyl-adamantane hydrochloride

Conditions	Yield
In water	72%

1,1-Dichloroethylene (75-35-4) + 3,5-dimethyl-1-bromoadamantane (941-37-7) → 2-(3,5-dimethyladamantan-1-yl)acetic acid (14202-14-3)

Conditions	Yield
With boron trifluoride diethyl etherate In sulfuric acid at 15℃;	70%
With sulfuric acid; boron trifluoride
Stage #1: 1,1-Dichloroethylene; 3,5-dimethyl-1-bromoadamantane With sulfuric acid In water at 10℃; for 1h; Stage #2: With boron trifluoride diethyl etherate In 1,1-dichloroethane; water at 10 - 15℃; for 2.5h;

2-Adamantanone (700-58-3) + 3,5-dimethyl-1-bromoadamantane (941-37-7) → 3,5-Dimethyl-[1,2']bi[tricyclo[decyl]-2'-ol

Conditions	Yield
With lithium sodium In diethyl ether at -25℃;	70%

3,5-dimethyl-1-bromoadamantane (941-37-7) + 3-hydroxy-trans-cinnamic acid (14755-02-3) → 3-((E)-2-((1s,3R,5S,7r)-3,5-dimethyladamantan-1-yl)vinyl)phenol

Conditions	Yield
With palladium diacetate; N-ethyl-N,N-diisopropylamine; triphenylphosphine In dimethyl sulfoxide at 28℃; for 24h; Inert atmosphere; Irradiation; Sealed tube; stereoselective reaction;	70%

Upstream product

• 876-53-9 1,3-dibromoadamantane 
• 707-37-9 3,5-dimethyladamantane-1-ol 
• 702-79-4 1,3-dimethyladamantane 
• 702-79-4 1,3-dimethyladamantane 
• 707-37-9 1,3-dimethyl-5-adamantanol 
• 19982-07-1 1-acetamido-3,5-dimethyladamantane 

Downstream Products

• 702-79-4 1,3-dimethyladamantane 
• 707-35-7 1,3,5-trimethyladamantane 
• 26919-42-6 (3,5-dimethyl-adamantan-1-yl)-methanol 
• 19982-07-1 1-acetamido-3,5-dimethyladamantane 
• 63971-25-5 3-amino-5,7-dimethyladamantan-1-ol 
• 707-36-8 1-chloro-3,5-dimethyl-adamantane 
• 351329-88-9 1-formamido-3,5-dimethyltricyclo[3.3.1.1^3,7]decane 
• 41100-52-1 memantine hydrochloride 
• 1619925-58-4 3,5-dimethyladamantyl hydrogenphenylphosphinate 
• 1344030-14-3 1,3-Me₂-5,7-Ad(CONHC₆H₅)2 
• 13928-68-2 5,7-dimethyladamantane-1,3-dicarboxylic acid 
• 1063713-00-7 4-bromo-2-(3,5-dimethyl-1-adamantyl)phenol 

Relevant articles and documents

Manganese/bipyridine-catalyzed non-directed C(sp3)–H bromination using NBS and TMSN3

A Mn(II)/bipyridine-catalyzed bromination reaction of unactivated aliphatic C(sp3)?H bonds has been developed using N-bromosuccinimide (NBS) as the brominating reagent. The reaction proceeded in moderate-to-good yield, even on a gram scale. The introduced bromine atom can be converted into fluorine and allyl groups.

PROCESS FOR PREPARATION OF MEMANTINE

The present invention provides an improved process of manufacturing 1-Bromo-3,5-dimethyladamantane compound of formula-IV starting from 1,3-dimethyladamantane that avoids use of liquid bromine and minimizes the use of hazardous chemicals. The present invention also provides use of 1-Bromo-3,5-dimethyladamantane prepared by the process of present invention in the process of producing Memantine hydrochloride and pharmaceutical compositions thereof.

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Novel rimantadine analog and synthetic method thereof

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1,3-diamino-phenyl -5,7-dimethyl-adamantane a synthesizing method

The invention relates to a synthetic method of 1, 3-diamidophenyl-5, 7-dimethyl adamantine. The synthetic method is characterized by comprising the following steps: synthesizing 1-bromine-3, 5-dimethyladamantane from 1, 3-dimethyladamantane, bromine, a catalyst and halogenated hydrocarbon solvents; performing reaction on 1-bromine-3, 5-dimethyladamantane, absolute ethyl alcohol and sodium hydroxide solutions to synthesize 1-hydroxyl-3, 5-dimethyladamantane; performing reaction on 1-hydroxyl-3, 5-dimethyladamantane and acetanilide to obtain 1, 3-bi(4-acetamidophenyl)-5, 7-dimethyladamantane; finally, hydrolyzing absolute ethyl alcohol, water and sodium hydroxide to obtain 1, 3-diamidophenyl-5, 7-dimethyladamantane. Products obtained in all steps in the preparation method do not need to be refined so that the purity can reach 99 percent; subsequent and complicated operation treatment on intermediates in all steps is not needed, and the intermediates can be used in the next reaction step. A diamine monomer prepared by using 1, 3-diamidophenyl-5, 7-dimethyladamantane is high in transparency and high in color index to ensure that a polyimide (PI) film increases the transparency, reduces the linear expansion coefficients, raising the glass transition temperature, and improves the refractive index, so that the production process of the PI film is simplified, and the investment of production equipment is greatly reduced.

Bromination of adamantane and its derivatives with tetrabromomethane catalyzed by iron compounds

Catalytic bromination of adamantane and its derivatives with tetrabromomethane catalyzed by iron compounds has been performed. The favorable ratio of catalyst and reagents and the conditions of a selective synthesis of bromine-substituted adamantanes have been developed.

Synthesis of 3,5-dimethyladamantan-1-ol by reaction of 1,3- dimethyladamantane with bromotrichloromethane and water in the presence of manganese complexes

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Evaluation of cyclopentyl methyl ether (CPME) as a solvent for radical reactions

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Synthesis and IR/MS study of 3,5-dimethyladamantanamine hydrochloride salt

This paper studied the synthesis of memantine hydrochloride characteristics by optimizing the synthetic route in the bromination of acid hydrolysis under the conditions of acetonitrile and the final salt formation reaction, so that memantine hydrochloride in an overall yield of the products from the 67.3 % reported in the literature increased to 81.5 %. Compared to 1,3-dimethyl adamantane and 3,5-dimethyladamantanamine, the infrared spectra showed the characteristic absorptions of 3,5-dimethyl-adamantanamine hydrochloride. Especially by the use of ESI method Spray ionization mass spectrometry analysis of fragments of memantine hydrochloride mass characteristics of ammonia compounds. By IR and MS studies to determine the spectrum of memantine hydrochloride microscopic molecular structure of ammonia.

PROCESS FOR MANUFACTURING ADAMANTANE DERIVATIVES WITH HIGH YIELD

The present invention pertains to process for the amidation of a substituted 1-bromo-adamantane comprising a step (0) of reacting a substituted adamantane with an excess of bromine to obtain a 1-bromo-adamantane and a step (i) of reacting said substituted 1-bromo-adamantane with an amide, wherein the substituted 1-bromo-adamantane is used in the form of a mixture comprising bromine as obtained in step (0), wherein in step (0) a bromine: substituted adamantane molar ratio of from [2.5:1] to less than [5:1] is employed.