7328-91-8

Basic information

• Product Name: 2,2-DIMETHYL-1,3-PROPANEDIAMINE
• Synonyms: 2,2-DIMETHYL-1,3-PROPANEDIAMINE;2,2-DIMETHYLPROPYLENEDIAMINE;1,3-DIAMINO-2,2-DIMETHYLPROPANE;RARECHEM AL BW 2308;NEOPENTANEDIAMINE;1,3-Propanediamine, 2,2-dimethyl-;2,2-dimethyl-3-propanediamine;2,2-Dimethyltrimethylenediamine
• CAS NO: 7328-91-8
• Molecular Formula: C₅H₁₄N₂
• Molecular Weight: 102.18
• EINECS: 230-819-0
• Product Categories: Amine Monomers;Monomers;Primary Amines
• Mol File: 7328-91-8.mol
• Article Data: 5

Chemical Properties

• Melting Point: 29-31 °C(lit.)
• Boiling Point: 152-154 °C(lit.)
• Flash Point: 117 °F
• Appearance: Colorless/Low Melting Solid
• Density: 0.851 g/mL at 25 °C(lit.)
• Vapor Pressure: 3.86mmHg at 25°C
• Refractive Index: n20/D 1.4566(lit.)
• Storage Temp.: Store below +30°C.
• PKA: 10.55±0.15(Predicted)
• Explosive Limit: 1.4-8.7%(V)
• CAS DataBase Reference: 2,2-DIMETHYL-1,3-PROPANEDIAMINE(CAS DataBase Reference)
• NIST Chemistry Reference: 2,2-DIMETHYL-1,3-PROPANEDIAMINE(7328-91-8)
• EPA Substance Registry System: 2,2-DIMETHYL-1,3-PROPANEDIAMINE(7328-91-8)

Safety Data

• Hazard Codes: C
• Statements: 10-34
• Safety Statements: 16-26-27-36/37/39-45
• RIDADR: UN 2921 8/PG 2
• WGK Germany: 1
• HazardClass: 8
• PackingGroup: II
• Hazardous Substances Data: 7328-91-8(Hazardous Substances Data)

Usage

Flammability and Explosibility

Flammable

InChI:InChI=1/C5H14N2/c1-5(2,3-6)4-7/h3-4,6-7H2,1-2H3

Synthetic route

2,2-dimethylmalonamide (41882-44-4) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
With dimethylsulfide borane complex In tetrahydrofuran for 2h; Heating;	75%

3-amino-2,2-dimethyl-propionitrile (67744-70-1) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
With methanol; nickel Hydrogenation;

2,2-dimethyl-1,3-diphthalimido-propane → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
With potassium hydroxide; water

2,2-dimethyl-1,3-dinitropropane (762-98-1) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
With hydrogenchloride; water; iron at 100℃; durch Reduktion;
With methanol; nickel under 30891.3 Torr; Hydrogenation;
With methanol; nickel at 50 - 75℃; under 51485.6 Torr; Hydrogenation;
With hydrogen; nickel

2,2-dimethyl-1,3-dinitropropane (762-98-1) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 2,2-dimethylmalonamide (41882-44-4)

Conditions	Yield
With ethanol; nickel at 60℃; under 51485.6 Torr; Hydrogenation;
With ethanol; nickel at 60℃; under 51485.6 Torr; Hydrogenation;

1,3-diazido-2,2-dimethyl-propane (31044-89-0) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
With lithium aluminium tetrahydride In tetrahydrofuran for 18h; Heating;

2,2-Dimethyl-1,3-propanediol (126-30-7) → 3-amino-2,2-dimethylpropan-1-ol (26734-09-8) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
With ammonia; hydrogen; Co-Fe catalyst at 210℃; under 37503 - 112509 Torr; Product distribution;

hydrogenchloride (7647-01-0) + 2-(5,5-dimethyl-hexahydro-pyrimidin-2-yl)-2-methyl-propionic acid amide (859065-87-5) + diethyl ether (60-29-7) + ethanol (64-17-5) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 2,2-dimethyl-3-oxo-propionic acid amide (as 2,4-dinitro-phenyl hydrazone isolated)

ethanol (64-17-5) + 2,2-dimethyl-1,3-dinitropropane (762-98-1) + Raney nickel → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 2,2-dimethylmalonamide (41882-44-4)

Conditions	Yield
at 60℃; under 51485.6 Torr; Hydrogenation;
at 60℃; under 51485.6 Torr; Hydrogenation;

hydrogenchloride (7647-01-0) + α-(nitromethyl)isobutyronitrile (114583-17-4) + iron powder → 2-(5,5-dimethyl-hexahydro-pyrimidin-2-yl)-2-methyl-propionic acid amide (859065-87-5) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 3-amino-2,2-dimethyl-propionitrile (67744-70-1) + aminopivalinamide (324763-51-1)

Conditions	Yield
at 60 - 70℃;
at 60 - 70℃;

methanol (67-56-1) + α-(nitromethyl)isobutyronitrile (114583-17-4) + palladium-CaCO3 → 2-(5,5-dimethyl-hexahydro-pyrimidin-2-yl)-2-methyl-propionic acid amide (859065-87-5) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 3-amino-2,2-dimethyl-propionitrile (67744-70-1) + aminopivalinamide (324763-51-1)

Conditions	Yield
Hydrogenation;
Hydrogenation;

methanol (67-56-1) + α-(nitromethyl)isobutyronitrile (114583-17-4) + Raney nickel → 2-(5,5-dimethyl-hexahydro-pyrimidin-2-yl)-2-methyl-propionic acid amide (859065-87-5) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 3-amino-2,2-dimethyl-propionitrile (67744-70-1) + aminopivalinamide (324763-51-1)

Conditions	Yield
Hydrogenation;
Hydrogenation;

α-(nitromethyl)isobutyronitrile (114583-17-4) + Raney nickel + methanolic NH3 → 2-(5,5-dimethyl-hexahydro-pyrimidin-2-yl)-2-methyl-propionic acid amide (859065-87-5) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 3-amino-2,2-dimethyl-propionitrile (67744-70-1) + aminopivalinamide (324763-51-1)

Conditions	Yield
at 100℃; Hydrogenation;
at 100℃; Hydrogenation;

2,2-Dimethylmalonyl chloride (5659-93-8) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 82 percent / 28percent NH3 2: 75 percent / BH3*SMe2 / tetrahydrofuran / 2 h / Heating View Scheme

2,2-dimethylmalonic acid (595-46-0) + l-trans-caronic acid → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
Multi-step reaction with 3 steps 1: 71 percent / SOCl2 / 20 h / Heating 2: 82 percent / 28percent NH3 3: 75 percent / BH3*SMe2 / tetrahydrofuran / 2 h / Heating View Scheme

α-(nitromethyl)isobutyronitrile (114583-17-4) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: iron; aqueous HCl / 60 - 70 °C 2: Raney nickel; methanol / Hydrogenation View Scheme

neopentyl glycol bis(benzenesulfonate) (31044-87-8) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: NaN3 / bis-(2-hydroxy-ethyl) ether / 16 h / 135 °C 2: LiAlH4 / tetrahydrofuran / 18 h / Heating View Scheme

2,2-Dimethyl-1,3-propanediol (126-30-7) → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
Multi-step reaction with 3 steps 1: pyridine / 24 h / 10 °C 2: NaN3 / bis-(2-hydroxy-ethyl) ether / 16 h / 135 °C 3: LiAlH4 / tetrahydrofuran / 18 h / Heating View Scheme

ethane-1,1,2-tricarboxylic acid (922-84-9) + platinum(II) chloride → 2,2-Dimethyl-1,3-diaminopropane (7328-91-8)

Conditions	Yield
With silver nitrate In sodium hydroxide; water

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + Chlorodiisopropylphosphane (40244-90-4) → N,N'-1,3-bis(P,P'-diisopropylthiophosphinic)-2,2-dimethylpropylene diamine (596106-62-6)

Conditions	Yield
Stage #1: 2,2-Dimethyl-1,3-diaminopropane; Chlorodiisopropylphosphane With N-ethyl-N,N-diisopropylamine In dichloromethane at 0 - 23℃; Stage #2: With sulfur at 80℃; for 0.5h;	100%
Stage #1: 2,2-Dimethyl-1,3-diaminopropane; Chlorodiisopropylphosphane With N-ethyl-N,N-diisopropylamine In dichloromethane at 0 - 25℃; Stage #2: With sulfur In dichloromethane at 20℃; for 2h;	72%
Stage #1: 2,2-Dimethyl-1,3-diaminopropane; Chlorodiisopropylphosphane With N-ethyl-N,N-diisopropylamine In dichloromethane at 20℃; Stage #2: With sulfur In dichloromethane at 20℃; for 2h;	68%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 4-methoxy-benzaldehyde (123-11-5) → C21H26N2O2 (1295636-73-5)

Conditions	Yield
In ethanol at 20℃; for 4h; Reflux;	100%
With formic acid In methanol for 24h; Reflux; Inert atmosphere;	54%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 3-methoxy-2-hydroxybenzaldehyde (148-53-8) → N,N′-bis(3-methoxysalicylidene)-2,2-dimethyl-1,3-propanediamine (188482-90-8)

Conditions	Yield
In methanol at 22℃; for 4h;	100%
In ethanol for 1h; Reflux;	92%
In ethanol for 1h; Reflux;	92%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + ethyl trifluoroacetate, (383-63-1) → N-(3-amino-2,2-dimethylpropyl)-2,2,2-trifluoroacetamide (1321622-57-4)

Conditions	Yield
In tetrahydrofuran at 0 - 20℃; for 15h; Inert atmosphere;	100%
In tetrahydrofuran at 20℃; for 14.5h; Cooling with ice;

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + C40H76N2O2(2+)*2NO3(1-) + silver(I) acetate (563-63-3) + cobalt(II) acetate (71-48-7, 917-69-1, 5931-89-5, 55881-15-7, 68931-68-0, 68931-69-1, 93029-27-7) → C87H163CoN6O4(4+)*4NO3(1-)

Conditions	Yield
Stage #1: 2,2-Dimethyl-1,3-diaminopropane; C40H76N2O2(2+)*2NO3(1-) In dichloromethane at 20℃; Stage #2: cobalt(II) acetate In dichloromethane at 20℃; for 12h; Stage #3: silver(I) acetate In dichloromethane for 12h;	100%

thiophene-2-carbaldehyde (98-03-3) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) → C15H18N2S2

Conditions	Yield
In ethanol at 20℃; for 4h; Reflux;	100%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + (1R)-dispiro[adamantane-2,3'-[1,2,4]trioxolane-5',1'-cyclohexan]-3'-yl (4-nitrophenyl)carbonate → (1R,3'R)-dispiro[adamantane-2,3'-[1,2,4]trioxolane-5',1'-cyclohexan]-3'-yl (3-amino-2,2-dimethylpropyl)carbamate

Conditions	Yield
With triethylamine In dichloromethane at 20℃; for 3h;	100%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + butane-2,3-dione mono-oxime (135636-66-7) → C13H24N4O2

Conditions	Yield
With calcium hydride In acetonitrile at 0℃; Reflux;	99.23%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 2-hydroxy-3-phenylbenzaldehyde (14562-10-8) → 1,3-diamino-2,2-dimethyl-N,N'-bis(3-phenylsalicylidene)propane

Conditions	Yield
In ethanol at 20℃;	99%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + salicylaldehyde (90-02-8) → 2,2′-((1E,1′ E)-((2,2-dimethylpropane-1,3diyl)bis(azaneylylidene))bis(methaneylylidene))diphenol

Conditions	Yield
In ethanol at 20℃;	99%
In methanol at 20℃; for 0.333333h;	75%
In methanol
In methanol for 2h; Reflux;
In methanol at 20℃; for 0.5h;

pent-4-enoic acid (591-80-0) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) → C15H26N2O2 (1446746-88-8)

Conditions	Yield
Stage #1: pent-4-enoic acid With dmap; dicyclohexyl-carbodiimide In dichloromethane at 0℃; for 0.5h; Stage #2: 2,2-Dimethyl-1,3-diaminopropane In dichloromethane at 20℃;	99%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 6-formyl-2,2'-bipyridine (134296-07-4) → C27H26N6

Conditions	Yield
In methanol for 3h;	99%

3-(tert-butyldimethylsilyl)-2-hydroxybenzaldehyde (140840-53-5) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) → N,N'-bis[3-(tert-butyldimethylsilyl)salicylidene]-2,2-dimethyl-1,3-propanediamine

Conditions	Yield
In ethanol at 20℃;	98%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + tert-butyl [4-(4,5-dihydro-1H-imidazol-2-yl)benzyl]methylcarbamate (1211569-73-1) → tert-butyl [4-(5,5-dimethyl-1,4,5,6-tetrahydropyrimidin-2-yl)benzyl]methylcarbamate (1211569-84-4)

Conditions	Yield
at 155℃; for 1h;	98%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 3,5-di-tert-butyl-2-hydroxybenzaldehyde (37942-07-7) → (2,2-dimethylpropandiyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol (175291-16-4)

Conditions	Yield
In ethanol at 20℃;	98%
In ethanol at 50 - 70℃; for 2.25h;	90%
	88%

lanthanum(III) nitrate hexahydrate + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + zinc(II) acetate dihydrate (5970-45-6) + 3,6-diformylcatechol (148063-59-6) → C39H42LaN6O6Zn3(3+)*3NO3(1-)

Conditions	Yield
Stage #1: lanthanum(III) nitrate hexahydrate; zinc(II) acetate dihydrate; 3,6-diformylcatechol In methanol; chloroform; water at 20℃; for 0.5h; Stage #2: 2,2-Dimethyl-1,3-diaminopropane In chloroform at 20℃; for 18h;	98%

3-amino-5-bromopyridine-2-carbonitrile (573675-27-1) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) → 5-bromo-2-(5,5-dimethyl-4,6-dihydro-1H-pyrimidin-2-yl)pyridin-3-amine

Conditions	Yield
In N,N-dimethyl acetamide at 160℃; Sealed tube;	98%

zinc(II) nitrate hexahydrate + cerium(III) acetate monohydrate + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 3,6-diformylcatechol (148063-59-6) → C39H42CeN6O6Zn3(3+)*3NO3(1-)

Conditions	Yield
Stage #1: zinc(II) nitrate hexahydrate; cerium(III) acetate monohydrate; 3,6-diformylcatechol In methanol; chloroform; water at 20℃; for 17h; Stage #2: 2,2-Dimethyl-1,3-diaminopropane In methanol at 20℃; for 1h;	98%

2-Hydroxy-1,4-naphthoquinone (83-72-7) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + (4-fluorophenyl)glyoxal (403-32-7) + 1,1-di(methylsulfanyl)-2-nitroethylene (13623-94-4) → 2-[6-(4-fluoro-phenyl)-3,3-dimethyl-8-nitro-1,2,3,4-tetrahydro-pyrrolo[1,2-a]pyrimidin-7-yl]-3-hydroxy-[1,4]naphthoquinone

Conditions	Yield
Stage #1: 2,2-Dimethyl-1,3-diaminopropane; 1,1-di(methylsulfanyl)-2-nitroethylene In ethanol; water for 4h; Reflux; Stage #2: 2-hydroxynaphtho-1,4-quinone; (4-fluorophenyl)glyoxal In ethanol; water at 60℃; for 0.0833333h; regioselective reaction;	97%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + (-)-menthyl 3-formyl-4-hydroxy-5-methoxybenzoate → C43H62N2O8

Conditions	Yield
In ethanol for 5h; Reflux;	97%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + bis(chlorotriazine) (201288-39-3) → C56H78N14O4 (321898-29-7)

Conditions	Yield
at 90℃;	96%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + Diphenylphosphinic chloride (1499-21-4) → N,N'-bis(P,P-diphenylphosphinoyl)-2,2-dimethyl-1,3-propanediamine (596106-64-8)

Conditions	Yield
With N-ethyl-N,N-diisopropylamine In dichloromethane at 0 - 20℃;	96%
With triethylamine at 0℃; for 6h;

[bis(1H-benzotriazol-1-yl)methylidene](4-chlorophenyl)amine (865075-67-8) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) → 4-chloro-N-[3,4,5,6-tetrahydro-5,5-dimethyl-1H-pyrimidin-2-ylidene]aniline

Conditions	Yield
In toluene for 1h; Heating;	96%

2-chloroethanal (107-20-0) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + potassium hydrogencarbonate (298-14-6) → (RS)-3,3-dimethylhexahydro[1,3]oxazolo[3,4-a]pyrimidin-6-one (1580482-20-7)

Conditions	Yield
In water at 20℃; for 10h; Green chemistry;	96%

3-(tert-butyldimethylsilyl)-2-hydroxybenzaldehyde (140840-53-5) + 2,2-Dimethyl-1,3-diaminopropane (7328-91-8) → C31H50N2O2Si2

Conditions	Yield
In ethanol at 20 - 80℃; for 2h; Inert atmosphere;	96%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + (E)-2-hydroxy-3-methoxy-5-( p-tolyldiazenyl)benzaldehyde → C20H26N4O2

Conditions	Yield
In methanol at 20℃; for 4h;	96%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + di-tert-butyl dicarbonate (24424-99-5) → di-tert-butyl 2,2-dimethylpropane-1,3-diyldicarbamate

Conditions	Yield
With triethylamine In dichloromethane at 0 - 20℃; Inert atmosphere;	96%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + C98H152O11 → C201H314N2O20

Conditions	Yield
With acetic acid In ethanol	96%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + acetone (67-64-1) → N,N'-diisipropyl-2,2-dimethyl-1,3-diaminopropane (31892-16-7)

Conditions	Yield
With hydrogen; palladium on activated charcoal In ethanol under 51714.8 Torr;	95%

2,2-Dimethyl-1,3-diaminopropane (7328-91-8) + 4-hydroxybenzimidic acid methyl ester hydrochloride (57943-60-9) → 4-(1,4,5,6-tetrahydro-5,5-dimethyl-2-pyrimidinyl)phenol

Conditions	Yield
In ethanol for 18h; cycloamynation; Pinner synthesis; Heating;	95%

Upstream product

• 67744-70-1 3-amino-2,2-dimethyl-propionitrile 
• 762-98-1 2,2-dimethyl-1,3-dinitropropane 
• 41882-44-4 2,2-dimethylmalonamide 
• 126-30-7 2,2-Dimethyl-1,3-propanediol 
• 64-17-5 ethanol 
• 922-84-9 ethane-1,1,2-tricarboxylic acid 
• 10025-65-7 platinum(II) chloride 
• 31044-87-8 neopentyl glycol bis(benzenesulfonate) 
• 114583-17-4 α-(nitromethyl)isobutyronitrile 
• 595-46-0 2,2-dimethylmalonic acid 
• 5659-93-8 2,2-Dimethylmalonyl chloride 
• 67-56-1 methanol 
• 7647-01-0 hydrogenchloride 
• 859065-87-5 2-(5,5-dimethyl-hexahydro-pyrimidin-2-yl)-2-methyl-propionic acid amide 

Downstream Products

• 151750-35-5 N,N'-bis(salicylidene)-2,2-dimethyl-1,3-diaminopropane 
• 97509-74-5 N-(5,5-Dimethyl-tetrahydro-pyrimidin-2-ylidene)-N'-[1-phenyl-eth-(E)-ylidene]-hydrazine 
• 97483-72-2 C₂₃H₃₀N₆S₂ 
• 184705-49-5 5,5-dimethyl-2-phenyl-1,4,5,6-tetrahydropyrimidine 
• 292606-35-0 N-tert-butyloxycarbonyl-2,2-dimethyl-1,3-propanediamine 
• 1026187-88-1 C₂₅H₃₈N₂O₆S₂ 
• 78134-14-2 N,N'-dibenzyl-2,2-dimethyl-1,3-diaminopropane 
• 17496-93-4 tetrahydro-5,5-dimethyl-2(1H)-pyrimidinone 
• 82175-38-0 5,5-dimethyltetrahydro-2(1H)-pyrimidinethione 
• 945914-86-3 2-(4-bromophenyl)-5,5-dimethyl-1,4,5,6-tetrahydropyrimidine 

Relevant articles and documents

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