593-90-8

Basic information

• Product Name: TRIMETHYLBORON
• Synonyms: Trimethylboroncolorlessgas;Trimethylboronelecgrcolorlessgas;TRIMETHYLBORON, 98.35+%, ELECTRONIC GRAD E;Trimethylboron,98%;Trimethylboron,elec.gr.(99.999%-B)PURATREM;99.9-B, PURATREM;TRIMETHYLBORON, ELEC. GR.;trimethylborine
• CAS NO: 593-90-8
• Molecular Formula: C₃H₉B
• Molecular Weight: 55.91
• EINECS: 209-816-3
• Product Categories: Chemical Synthesis;Compressed and Liquefied GasesVapor Deposition Precursors;Gases;Precursors by Metal;Synthetic Reagents;metal alkyl;Chemical Synthesis;CVD and ALD Precursors by Metal;Materials Science;Micro/NanoElectronics;Specialty Gases;Synthetic Reagents;Vapor Deposition Precursors
• Mol File: 593-90-8.mol

Chemical Properties

• Melting Point: -161,5°C
• Boiling Point: -20,2°C
• Flash Point: °C
• Appearance: /liquid
• Density: 0,625 g/cm3
• Vapor Pressure: 907mmHg at 25°C
• Refractive Index: 1.311
• CAS DataBase Reference: TRIMETHYLBORON(CAS DataBase Reference)
• NIST Chemistry Reference: TRIMETHYLBORON(593-90-8)
• EPA Substance Registry System: TRIMETHYLBORON(593-90-8)

Safety Data

• Hazard Codes: F,C
• Statements: 11-17-34
• Safety Statements: 9-16-23-45-43-36/37/39-26-7
• RIDADR: 3160
• HazardClass: 2.3
• Hazardous Substances Data: 593-90-8(Hazardous Substances Data)

Usage

Uses

Precursor to boron carbide thin films by chemical vapor deposition (CVD).1

InChI:InChI=1/C3H9B/c1-4(2)3/h1-3H3

Synthetic route

(methyl)3boron*NH3 → trimethylborane (593-90-8) + ammonia (7664-41-7)

Conditions	Yield
at 130.0°C, 74.1 Torr equilibrium;	A 99.6% B 99.6%
at 130.0°C, 74.1 Torr equilibrium;	A 99.6% B 99.6%
at 54.8°C, 57.6 Torr equilibrium;	A 90.8% B 90.8%
at 54.8°C, 57.6 Torr equilibrium;	A 90.8% B 90.8%

Triisopropyl borate (5419-55-6) + methyllithium (917-54-4) → dimethylisopropoxyborane + trimethylborane (593-90-8) + diisopropoxymethylborane (86595-27-9)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 1% B <1 C 98%

tri-sec-butylborate (22238-17-1) + methyllithium (917-54-4) → (CH3)2B(OCH(CH3)CH2CH3) + CH3B(OCH(CH3)CH2CH3)2 (86595-29-1) + trimethylborane (593-90-8)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 1% B 98% C <1

triisobutyl borate (13195-76-1) + methyllithium (917-54-4) → (CH3)2B(OCH2CH(CH3)2) + CH3B(OCH2CH(CH3)2)2 (86595-30-4) + trimethylborane (593-90-8)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 1% B 98% C <1

methyllithium (917-54-4) + 2,4,4,5,5-pentamethyl-[1,3,2]dioxaborolane (94242-85-0) → (CH3)2BOC(CH3)2C(CH3)2OH (97782-68-8) + trimethylborane (593-90-8)

Conditions	Yield
With hydrogenchloride In diethyl ether byproducts: LiCl; 1 equiv of MeLi slowly adding to a soln. of the boronic ester at -78°C, stirring for 3 h at the same temp., 1 equiv of anhydrous HCl in Et2O adding, warming to room temp., stirring for 15 min; the content was detd. by (11)B NMR spectrum;	A 98% B <1

trimethyl-borane; compound with trimethylamine (856617-42-0) → trimethylborane (593-90-8) + trimethylamine (75-50-3)

Conditions	Yield
at 111.3°C, 64.5 Torr equilibrium;	A 96% B 96%
at 111.3°C, 64.5 Torr equilibrium;	A 96% B 96%
at 65.8°C, 47.5 Torr equilibrium;	A 63.8% B 63.8%

methyllithium (917-54-4) + diisopropoxymethylborane (86595-27-9) → dimethylisopropoxyborane + trimethylborane (593-90-8)

Conditions	Yield
With hydrogenchloride In diethyl ether byproducts: LiCl, 2-propanol; 2 equiv of MeLi slowly adding to a soln. of the boronic ester at -78°C, stirring for 3 h at the same temp., 1 equiv of anhydrous HCl in Et2O adding, warming to room temp., stirring for 15 min; the content was detd. by (11)B NMR spectrum;	A 95% B <1
With hydrogenchloride In diethyl ether byproducts: LiCl, 2-propanol; 1 equiv of MeLi slowly adding to a soln. of the boronic ester at -78°C, stirring for 3 h at the same temp., 1 equiv of anhydrous HCl in Et2O adding, warming to room temp., stirring for 15 min; the content was detd. by (11)B NMR spectrum;	A 95% B <1

methyllithium (917-54-4) + 2-methyl-[1,3,2]dioxaborinane (51901-48-5) → (CH3)2BO(CH2)3OH (765242-40-8) + trimethylborane (593-90-8)

Conditions	Yield
With hydrogenchloride In diethyl ether byproducts: LiCl; 2 equiv of MeLi slowly adding to a soln. of the boronic ester at -78°C, stirring for 3 h at the same temp., 1 equiv of anhydrous HCl in Et2O adding, warming to room temp., stirring for 15 min; the content was detd. by (11)B NMR spectrum;	A 92% B <7

bis[tert-butyl(dimethylboryl)amino]methylphosphanoxide (62948-84-9) → trimethylborane (593-90-8) + 1,3-di-tert-butyl-2,4-dimethyl-1,3,2,4-diazaphosphaboretidine-2-oxide (62948-89-4)

Conditions	Yield
In neat (no solvent) heating at 160-170°C for 5 h in a stream of N2 with condensationof the volatiles in a trap cooled at -78°C;; distn.; elem. anal.;;	A 88% B 75%

methylmagnesium bromide (75-16-1) + boron trichloride (10294-34-5) → trimethylborane (593-90-8)

Conditions	Yield
In diethyl ether at room temp. for 2 h, molar ratio BCl3:ether:MeMgBr01:2:3; by fractional condensation;	87%
In diethyl ether at room temp. for 2 h, molar ratio BCl3:ether:MeMgBr01:2:3; by fractional condensation;	87%

dimethylboron bromide (5158-50-9) + bis(tert-butylamino)dimethylsilane (17940-08-8) → trimethylborane (593-90-8) + 1,3-di-tert-butyl-2,2,4-trimethyl-1,3,2,4-diazasilaboretidine (62948-94-1)

Conditions	Yield
With n-butyllithium In hexane; cyclohexane under N2 atmosphere; lithiation of the amine with n-BuLi in hexane; refluxing for 20 h; dropwise addn. of a soln. of B compd. in cyclohexane tothe suspn. of the Li compd. at -78°; slow warming to room temp.;; filtration; removal of volatiles from filtrate; fractional distn.; elem. anal.;;	A 83.5% B 67%

boric acid tributyl ester (688-74-4) + methyllithium (917-54-4) → (CH3)2B(OC4H9) + trimethylborane (593-90-8) + methyldi-n-butoxyborane (86595-28-0)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 9% B <1 C 82%

trimethyl-borane; compound with methylamine (854457-30-0) → trimethylborane (593-90-8) + methylamine (74-89-5)

Conditions	Yield
at 130.0°C, 77.4 Torr equilibrium;	A 81.95% B 81.95%
at 130.0°C, 77.4 Torr equilibrium;	A 81.95% B 81.95%
at 85.4°C, 52.5 Torr equilibrium;	A 38.86% B 38.86%
at 85.4°C, 52.5 Torr equilibrium;	A 38.86% B 38.86%

methylmagnesium bromide (75-16-1) + boron tribromide (10294-33-4) → trimethylborane (593-90-8)

Conditions	Yield
In diethyl ether	80%
In diethyl ether	80%
In benzene
In benzene

2,8-dibromo-3,4,6,7-tetrathia-1-aza-2,5,8-triborabicyclo{3.3.0(1,5)}octane (124665-16-3) + bis(dimethylboryl)disulphane (27484-88-4) → 9-methyl-2,3,5,6,8,10-hexathia-11-aza-1,4,7,9-tetraboratricyclo{6.2.1.0(1,11)}undecane (124665-19-6) + trimethylborane (593-90-8) + dimethylboron bromide (5158-50-9) + 3,5-dimethyl-1,2,4-trithia-3,5-diborolane (25592-09-0)

Conditions	Yield
In toluene N2 atmosphere; addn. of soln. of (Me2BS)2 to soln. of BN(BBr2)2 (room temp., stirring), heating (70°C, 36 h); sepn. of solid, removal of volatiles, sepn. of educt (sublimation, 110°C, 1.3 Pa); elem. anal.;	A 76% B n/a C n/a D n/a

trimethyl-borane; compound with dimethylamine (856622-99-6) → trimethylborane (593-90-8) + dimethyl amine (124-40-3)

Conditions	Yield
at 125.6°C, 66.3 Torr equilibrium;	A 74.2% B 74.2%
at 125.6°C, 66.3 Torr equilibrium;	A 74.2% B 74.2%
at 85.1°C, 45 Torr equilibrium;	A 31.6% B 31.6%
at 85.1°C, 45 Torr equilibrium;	A 31.6% B 31.6%

Triisopropyl borate (5419-55-6) + Trimethylboroxine (823-96-1) → trimethylborane (593-90-8) + diisopropoxymethylborane (86595-27-9)

Conditions	Yield
In tetrahydrofuran	A n/a B 70%

triethyl borate (150-46-9) + methyllithium (917-54-4) → diethoxymethylborane (86595-26-8) + trimethylborane (593-90-8) + Dimethan-borinsaeure-ethylester (86610-16-4)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 65% B 7% C 10%

CH3B(O-t-C4H9)2 (819-38-5) + methyllithium (917-54-4) → trimethylborane (593-90-8) + Dimethylborinsaeure-tert.-butylester (38109-66-9)

Conditions	Yield
With hydrogenchloride In diethyl ether byproducts: LiCl, 2-propanol; 1 equiv of MeLi slowly adding to a soln. of the boronic ester at -78°C, stirring for 3 h at the same temp., 1 equiv of anhydrous HCl in Et2O adding, allowing to warm to room temp., stirring for 15 min; the content was detd. by (11)B NMR spectrum;	A 32% B 58%

tetramethyl diborane (21482-59-7) + ethene (74-85-1) → trimethylborane (593-90-8) + (dimethyl)trifluoropropylborane (819-58-9) + Methyl-bis-<3,3,3-trifluor-propyl>-boran (689-46-3)

Conditions	Yield
	A 30% B 45% C 8%
	A 30% B 45% C 8%

chlorodimethoxyborane (868-81-5) + methyllithium (917-54-4) → trimethylborane (593-90-8) + methoxy-dimethyl-borane (4443-43-0) + bis(methoxy)methylborane (7318-81-2)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 16% B 6% C 43%

boric acid tribenzyl ester (2467-18-7) + methyllithium (917-54-4) → (CH3)2B(OCH2C6H5) + CH3B(OCH2C6H5)2 + trimethylborane (593-90-8)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 25% B 42% C 4%

diborane + dimethyl zinc(II) (544-97-8) → zinc dihydride (14018-82-7) + trimethylborane (593-90-8) + methylzinc tetrahydroborate

Conditions	Yield
In neat (no solvent) (exclusion of moisture); room temp., 16 h; purifn. by trap-to-trap distn.;	A n/a B n/a C 40%

Trimethyl borate (121-43-7) + trimethylaluminum (75-24-1) → trimethylborane (593-90-8)

Conditions	Yield
In mineral oil B(OCH3)3 condensed onto Al(CH3)3 soln. with -196°C trap, opened to closed vol., warmed slowly to room temp. with stirring, repeated twice; pumped into -196°C trap, passed through -132°C into -196°C trap;	38%

tetramethyl diborane (21482-59-7) + ethene (74-85-1) → trimethylborane (593-90-8) + dimethylethylborane (1113-22-0) + triethyl borane (97-94-9) + methyldiethylborane (1115-07-7)

Conditions	Yield
	A 25% B 34% C 0.5% D 19%
	A 25% B 34% C 0.5% D 19%

dimethylboron bromide (5158-50-9) + 1,1,1,3,3,3-hexamethyl-disilazane (999-97-3) → trimethylborane (593-90-8) + 2,4,6-Trimethyl-[1,3,5,2,4,6]triazatriborinane (5314-85-2) + bis(dimethylboryl)methylamine (19163-15-6)

Conditions	Yield
byproducts: (CH3)3SiBr; 50°C, 20 h, in closed tube;	A n/a B n/a C 34%

methyllithium (917-54-4) + boron trichloride (10294-34-5) → trimethylborane (593-90-8) + methoxy-dimethyl-borane (4443-43-0) + bis(methoxy)methylborane (7318-81-2)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 32% B 3% C <1

2-bromo-1,3,2-benzodioxaborole (51901-49-6) + methyllithium (917-54-4) → (CH3)2BOC6H4OH (97782-69-9) + trimethylborane (593-90-8)

Conditions	Yield
With hydrogenchloride In diethyl ether byproducts: LiCl; 1 equiv of MeLi slowly adding to a soln. of the boronic ester at -78°C, stirring for 3 h at the same temp., 1 equiv of anhydrous HCl in Et2O adding, warming to room temp., stirring for 15 min; the content was detd. by (11)B NMR spectrum;	A 20% B 30%

fluorodimethoxyborane (367-46-4) + methyllithium (917-54-4) → trimethylborane (593-90-8) + methoxy-dimethyl-borane (4443-43-0) + bis(methoxy)methylborane (7318-81-2)

Conditions	Yield
With hydrogenchloride In diethyl ether under N2; to cold (-78 °C) soln. of boron compd. in Et2O slowly added MeLi, stirred for 0.5 h, warmed to room temp., stirred for 0.5 h,Li(BMe4) detected by (11)B NMR, cooled to 0 °C, added soln. of HCl in Et2O, stirred for 15 min, warmed; not isolated, monitored by (11)B NMR;	A 28% B <1 C 10%

methyllithium (917-54-4) + 2-methyl-1,3,2-dioxaborolane (37003-57-9) → (CH3)2BO(CH2)2OH (97782-66-6) + trimethylborane (593-90-8)

Conditions	Yield
With hydrogenchloride In diethyl ether byproducts: LiCl; 1 equiv of MeLi slowly adding to a soln. of the boronic ester at -78°C, stirring for 3 h at the same temp., 1 equiv of anhydrous HCl in Et2O adding, warming to room temp., stirring for 15 min; the content was detd. by (11)B NMR spectrum;	A 21% B 26%

trimethylborane (593-90-8) + imidazolyl sodium (5587-42-8) → Na(1+)*C3H3N2(B(CH3)2)2(1-)*2C4H8O = Na[C3H3N2(B(CH3)2)2]*2C4H8O

Conditions	Yield
In tetrahydrofuran (Ar); warming from -78°C to room temp. (10 h); evapn.; elem. anal.;	99%

trimethylborane (593-90-8) + (tert-butylimino)(2,2,6,6-tetramethylpiperidino)borane (89201-97-8) → [(tert-butyl)(methyl(2,2,6,6-tetramethylpiperidino)boryl)amino]dimethylborane

Conditions	Yield
In hexane	97%
In hexane Schlenk technique, a soln. of iminoborane frozen at -196°C, borancondenced onto it, allowed to slowly thaw, stirred for 4 h; solvent removed (50 Torr); elem. anal.;	97%

boron trioxide + trimethylborane (593-90-8) → Trimethylboroxine (823-96-1)

Conditions	Yield
In neat (no solvent) synthesis of small amounts: condensation of 0.061 mol B(CH3)3 onto 0.061mol B2O3 (-192 °C), heating in a sealed tube at 300°C for 6h;; condensation in vac. into a trap at -78°C;;	96%
In neat (no solvent) synthesis of small amounts: condensation of 0.061 mol B(CH3)3 onto 0.061mol B2O3 (-192 °C), heating in a sealed tube at 300°C for 6h;; condensation in vac. into a trap at -78°C;;	96%

trimethylborane (593-90-8) + dichloroborane (10325-39-0) + boron trichloride (10294-34-5) → dichloro-methyl-borane (7318-78-7)

Conditions	Yield
at ambient temp. 24 h in presence of 1 vol.% HBCl2;	95%
at ambient temp. 24 h in presence of 1 vol.% HBCl2;	95%

trimethylborane (593-90-8) + (S,S)-(-)-1,2-dicyclohexyl-ethane-1,2-diol (120850-91-1) → (4S,5S)-4,5-dicyclohexyl-2-methoxy-1,3,2-dioxaborolane

Conditions	Yield
In neat (no solvent) byproducts: methanol; Ar-atmosphere; stirring; distg.;	95%

trimethylborane (593-90-8) + boron tribromide (10294-33-4) → dimethylboron bromide (5158-50-9)

Conditions	Yield
With alkene; tetraethyldiborane(6) react. of two equiv B(CH3)3 with one equiv BBr3 at room temp., decompn. of catalyst with alkene; distn.;	91%
tetraethyldiborane(6)

trimethylborane (593-90-8) + 2-[bis(2-hydroxyethyl)amino]-1,1-diphenyl-1-ethanol → 3,3-diphenylboratrane (928853-47-8)

Conditions	Yield
In chloroform (Ar), Me3B added to soln. of ligand in CHCl3, stirred for 24 h at room temp.; fconcd.(vac.), pptd.(pentane), filtered, washed (pentane), dried (vac.);	90%

2,3-dimethyl-2,3-butane diol (76-09-5) + trimethylborane (593-90-8) + 1,5-anhydro-2-deoxy-4,6-O-bis(tert-butylsilylidene)-3-O-triisopropylsilyl-D-arabino-hex-1-enitol (262266-33-1) → (1,5-anhydro-2-deoxy-4,6-O-bis(tert-butylsilylidene)-3-O-triisopropylsilyl-D-arabino-hex-1-enitol)boronic acid pinacol ester (842132-50-7)

Conditions	Yield
Stage #1: 1,5-anhydro-2-deoxy-4,6-O-bis(tert-butylsilylidene)-3-O-triisopropylsilyl-D-arabino-hex-1-enitol With n-butyllithium In tetrahydrofuran; hexane at -78 - 0℃; Inert atmosphere; Large scale; Stage #2: trimethylborane In tetrahydrofuran at -78℃; for 1h; Inert atmosphere; Large scale; Stage #3: 2,3-dimethyl-2,3-butane diol In toluene at 20℃; for 12h; Large scale;	90%

trimethylborane (593-90-8) + methyl 4-hydroxy-1-chloro-7-phenoxyisoquinoline-3-carboxylate (1421312-33-5) → 1-methyl-4-hydroxy-7-phenoxyisoquinoline-3-carboxylic acid (1421312-35-7)

Conditions	Yield
Stage #1: trimethylborane; methyl 4-hydroxy-1-chloro-7-phenoxyisoquinoline-3-carboxylate With bis-triphenylphosphine-palladium(II) chloride; sodium phosphate In 2-methoxy-ethanol; water at 90 - 100℃; for 4h; Stage #2: With hydrogenchloride In water at 20 - 30℃; pH=2 - 3;	88%

trimethylborane (593-90-8) + trimethylsilyllithium (18000-27-6) → Li(1+)*B(Si(CH3)3)(CH3)3(1-)=Li{B(Si(CH3)3)(CH3)3} (72442-81-0)

Conditions	Yield
In hexane at -196°C in high vac., pptn. during warming up; the solvent was decanted, the product was washed with pentane, then dissolved in benzene and crystd. with pentane; elem. anal.;	86%

trimethylborane (593-90-8) + methyl (4-hydroxy-1-chloro-7-phenoxyisoquinoline-3-carboxamido)acetate → [(4-hydroxy-1-methyl-7-phenoxy-isoquinoline-3-carbonyl)-amino]-acetic acid

Conditions	Yield
With tetrakis(triphenylphosphine) palladium(0); water; potassium carbonate In ethanol at 110℃; for 4h;	86%

dodecacarbonyl-triangulo-triruthenium (15243-33-1) + trimethylborane (593-90-8) + potassium hydride → K(1+)*HRu3(CO)11(1-)=KHRu3(CO)11 (80662-65-3)

Conditions	Yield
In tetrahydrofuran byproducts: CO; distg. of THF onto mixt. of Ru3(CO)12 and KH at -78°C in inert atmosphere, distg. of B(CH3)3 at -196°C, warming to 25°C, CO evolves, the soln. turns bright red; evapn. in vac. after 2 h, dissolving in min. amt. of CH2Cl2, addn. of hexane, filtn., washing (hexane);	83%

trimethylborane (593-90-8) + erythro-2-[bis(2-hydroxyethyl)amino]-1,2-diphenyl-1-ethanol → erythro-3,4-diphenylboratrane

Conditions	Yield
In chloroform (Ar), Me3B added to soln. of ligand in CHCl3, stirred for 24 h at room temp.; filtered, washed (CHCl3), dried (vac.);	82%

trimethylborane (593-90-8) + 1-phenyl-2-methylpropane (538-93-2) + Ethyl oxalyl chloride (4755-77-5) → ibuprofen (15687-27-1)

Conditions	Yield
Stage #1: 1-phenyl-2-methylpropane; Ethyl oxalyl chloride With aluminum (III) chloride Stage #2: trimethylborane With phosphorous acid trimethyl ester Stage #3: With lithium hydroxide	82%

trimethylborane (593-90-8) + (dimethylamino)dimethylphosphine (683-84-1) → Tetramethylborazen (1113-30-0)

Conditions	Yield
byproducts: (CH3)3B*P(CH3)3; in 77 day;	78%
byproducts: (CH3)3B*P(CH3)3; in 77 day;	78%

2,3-dimethyl-2,3-butane diol (76-09-5) + trimethylborane (593-90-8) + diisopropylamine (108-18-9) + 1,2-dibromomethane (74-95-3) → 2-(dibromomethyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (87921-48-0)

Conditions

Yield

With n-butyllithium; hydrogen bromide In tetrahydrofuran; diethyl ether; hexane (i-Pr)2NH in ether mixed with n-BuLi in n-hexane at 0°C, THF added, cooled to -100°C, CH2Br2 in THF added under stirring over 1 h, kept for 30 min at this temp., BMe3 added, after 40 min aq. HBr added at -100°C, warmed to room temp.; filtered, washed (ether), concd., residue taked up (ether), Me2C(OH)C(OH)Me2 added, petroleum ether added, stirred for 1 h, org. phase separated and washed (H2O, 4 times), dried (Na2SO4), concd., distilled at 0.5 Torr (100-110°C); elem. anal.;

77%

Upstream product

• 917-64-6 methyl magnesium iodide 
• 121-43-7 Trimethyl borate 
• 74-87-3 methylene chloride 
• 75-16-1 methylmagnesium bromide 
• 150-46-9 triethyl borate 
• 544-97-8 dimethyl zinc(II) 
• 5846-37-7 dimethylvinylborane 
• 5856-68-8 methyldivinylborane 
• 75-24-1 trimethylaluminum 
• 1803-36-7 chlorodimethylborane 
• 7318-78-7 dichloro-methyl-borane 
• 7732-18-5 water 
• 60-29-7 diethyl ether 
• 5419-55-6 Triisopropyl borate 

Downstream Products

• 17933-09-4 dimethyl iodoborane 
• 4011-26-1 (phenylamino)dimethylborane 
• 747-80-8 2,4,6-trimethyl-1,3,5-triphenyl-borazine 
• 2179-90-0 2-tert-butyl-1,3-diphenyl-[1,3,2]diazaborolidine 
• 2169-38-2 lithium tetramethylborate^(1-) 
• 7216-97-9 dimethylborane 
• 22400-31-3 2,3,3-trimethyl-4,5-diphenyl-3,4-dihydro-2H-[1,4,2]diazaborole; compound with N-(1-dimethylboranyl-ethylidene)-aniline (1:1) 
• 612-00-0 1,1'-ethylidenebis-benzene 
• 101-81-5 Diphenylmethane 
• 519-73-3 triphenylmethane 
• 5271-39-6 Triphenylethan 
• 281-23-2 adamantane 
• 768-91-2 1-methyl-adamantane 
• 96532-45-5 (1R,3R)-3-Benzyloxymethyl-1,2,2-trimethyl-cyclopropanol 

Relevant articles and documents

Indirect nuclear spin-spin coupling constants 1J( 17O,11B). First observation and calculation using density functional theory (DFT)

Coupling constants 1J(17O,11B) of borates, borane adducts and boranes with boron-oxygen bonds have been calculated on the basis of optimised molecular structures using the B3LYP/6-311+G(d,p) level of theory. This indicates that such coupling constants can be of either sign and that their magnitudes can be rather small. Since both 11B and 17O are quadrupole nuclei, it is therefore difficult to measure representative data. In the cases of trimethoxyborane and tetraethyldiboroxanes, it proved possible to obtain experimental data 1J( 17O,11B) (22 and 18 Hz) by measurement of 17O NMR spectra at high temperature (120 °C and 160 °C) respectively. The magnitude of these coupling constants is in reasonable agreement with calculated data. In the case of the diboroxane, this points towards a bond angle B-O-B more close to 180° than to 140°.

Mechanochemical reactions of alkali borohydride with CO2 under ambient temperature

Many efforts have been made to study the reactions of the borohydride with CO2 in solution. However, it is scarce to achieve the hydrogenation of CO2 using borohydrides as hydrogen source by the solid-gas direct reaction in the condition of ball milling under ambient temperature. Herein, we investigated the solid-gas noncatalytic reaction of ABH4 (A = Li or Na) with CO2 under mechanochemical conditions for the first time. It is found that hydrogen and trimethylborane are formed in the gas phase, as well as borate, formate, and methoxy species are formed in the solid phase.

Nickel-Catalyzed CO2Rearrangement of Enol Metal Carbonates for the Efficient Synthesis of β-Ketocarboxylic Acids

4-Methylene-1,3-dioxolan-2-ones underwent oxidative addition of a Ni0catalyst in the presence of Me2Al(OMe), followed by a coupling reaction with alkynes, to form δ,?-unsaturated β-ketocarboxylic acids with high regio- and stereoselectivity. The reaction proceeds by [1,3] rearrangement of an enol metal carbonate intermediate and the formal reinsertion of CO2.

Nucleophilicity of Alkyl Zirconocene and Titanocene Precatalysts, and Kinetics of Activation by Carbenium Ions and by B(C6F5)3

Kinetics of activation of methyl and benzyl metallocene precatalysts by benzhydrylium ions, tritylium ions, and triarylborane B(C6F5)3were measured spectrophotometrically. The rate constants correlate linearly with the electrophilicity parameter E of the benzhydrylium and tritylium ions employed, allowing us to determine the σ-nucleophilicities of the metal–carbon bond of several zirconocenes and titanocenes. Bridging, substitution, metal, and ligand effects on the rates of metal–alkyl bond cleavage (M=Zr, Ti) were studied and structure–reactivity correlations were used to predict the kinetics of generation of metallocenium ions pairs, which are active catalysts in polymerization reactions and are highly electrophilic Lewis acids in frustrated Lewis pair catalysis.

Aluminum Hydride Catalyzed Hydroboration of Alkynes

An aluminum-catalyzed hydroboration of alkynes using either the commercially available aluminum hydride DIBAL-H or bench-stable Et3Al?DABCO as the catalyst and H-Bpin as both the boron reagent and stoichiometric hydride source has been developed. Mechanistic studies revealed a unique mode of reactivity in which the reaction is proposed to proceed through hydroalumination and σ-bond metathesis between the resultant alkenyl aluminum species and HBpin, which acts to drive turnover of the catalytic cycle.

Nickel-catalyzed multicomponent coupling of alkyne, buta-1,3-diene, and dimethylzinc under carbon dioxide

A nickel catalyst promoted the coupling of alkynes with buta-1,3-diene and dimethylzinc under carbon dioxide to provide (5E,8Z)-2-vinyldeca-5,8-dienoic acids with high regio- and stereo selectivity. Georg Thieme Verlag Stuttgart. New York.

Structure, dynamics, and polymerization activity of zirconocenium ion pairs generated with boron-C6F5 compounds and Al 2R6

Figure Persented: The activation reaction of the olefin polymerization precatalyst Cp*2ZrMe2 with a boron-C 6F5 compound (B(C6F5)3, [Ph3C][B(C6F5)4]) and an aluminum alkyl species (Al2Me6, Al2iBu 6) is studied by NMR spectroscopy in order to determine the nature of the ion pairs that are formed preferentially. We show that a mixture of ion pairs with general formula Cp*2Zr(Me)-μ-Me-E(C 6F5)3-xRx (E = Al, B; x = 0, 1; R = Me, iBu) (1, 2a/b, 4) is generated due to a rapid transfer of pentafluorophenyl groups from boron to aluminum. Therefore, the molecular ratio of the activators determines the final composition of the ion pairs present in solution. When the pentafluorophenyl group transfer is suppressed, the ion pair Cp*2Zr-(μ-Me)2-AlMe2 (5) forms irrespective of the reagent ratio. The high dynamics of these solutions is demonstrated by DNMR studies. Gibbs free energies of activation were determined of 13.6(12) kcal mol-1 at 298 K for the cocatalyst exchange of ion pair Cp*2Zr(Me)-μ-Me-Al(C6F5) 2Me (2a) and 13(2) kcal mol-1 at 298 K for the methyl exchange in Al2(C6F5)xMe 6-x (x = 0, 1). Due to the stability of the ion pairs generated from the Cp*2ZrMe2 precatalyst at temperatures relevant for polymerization, correlations between activities in ethylene polymerization and the nature of the ion pairs can be established. All solutions containing the various ion pairs were found to be catalytically active in ethylene polymerization except that containing the ion pair 2a, which was attributed to the reduced Lewis acidity of the abstractor, as supported by DFT calculations.

GASEOUS DIELECTRICS WITH LOW GLOBAL WARMING POTENTIALS

A dielectric gaseous compound which exhibits the following properties: a boiling point in the range between about ?20° C. to about ?273° C.; non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative standard enthalpy of formation (dHf0); a toxicity level such that when the dielectric gas leaks, the effective diluted concentration does not exceed its PEL; and a dielectric strength greater than air.

Synthesis and structure of cyclic trinuclear zinc disiloxides

The synthesis and structure of the new disilane-1,2-diol [(Me 3Si)2SiOH]2 (2b) and the trinuclear zinc disiloxides of the formula [Me2Si{(Me3Si)2SiO} 2]2Zn3Me2 (3a), [{(Me 3Si)2Si-O)2]2Zn3Me 2 (3b) and [E-{Me(Me3Si)3SiSiO} 2]2Zn3Me2 (3c) are reported. Compounds 3a-c were prepared by reactions of the corresponding silanedioles 2a-c with ZnMe2. The results of an X-ray structure analysis of 3b reveal an almost perfectly planar spirocyclic Zn3Q4 core with a square-planar geometry of the inner Zn2+ ion, whereas in 3a,c the inner zinc ions are distorted tetrahedral. Upon treatment with B(C 6F5)3, compounds 3b,c have been converted quantitatively into the complexes [{(Me3Si)2SiO} 2]2Zn3(C6F5)2 (4b) and [E-{Me(Me3Si)3SiSiO}2] 2Zn3(C6F5)2 (4c). Wiley-VCH Verlag GmbH & Co. KGaA, 2007.

PROCESS FOR SYNTHESIS OF DIALKOXYORGANOBORANES

The invention relates to a process for the synthesis of dialkoxyorganoboranes, in particular to a process for the synthesis of dialkoxyorganoboranes by an ester exchange reaction. Moreover, the invention relates to a process for the synthesis of organo-oxazaborolidine catalysts (organo-CBS) and of trialkylboroxins. Furthermore, the invention relates to methods of using dialkoxyorganoboranes for the preparation of organo-CBS catalysts and in Suzuki-type coupling reactions.