112022-81-8

Basic information

• Product Name: (S)-3,3-Diphenyl-1-methylpyrrolidino[1,2-c]-1,3,2-oxazaborole
• Synonyms: (S)-1-METHYL-3,3-DIPHENYL-TETRAHYDRO-PYRROLO[1,2C][1,3,2]OXAZABOROLE;(S)-5,5-DIPHENYL-2-METHYL-3,4-PROPANO-1,3,2-OXAZABOROLIDINE;(S)-(-)-2-METHYL-CBS-OXAZABOROLIDINE;(S)-2-METHYL-CBS-OXAZABOROLIDINE;(S)-2-METHYL-CBS-OXAZABOROLIDINE MONOHYDRATE;(S)-3,3-Diphenyl-1-methylpyrrolidino[1,2-c]-1,3,2-oxazaborole;(S)-3,3-DIPHENYL-1-METHYLTETRAHYDRO-1H,3H-PYRROLO[1,2-C][1,3,2]OXAZABOROLE;(S)-3,3-DIPHENYL-1-METHYLTETRAHYDRO-3H-PYRROLO-[1,2-C][1,3,2]OXAZABOROLE
• CAS NO: 112022-81-8
• Molecular Formula: C₁₈H₂₀BNO
• Molecular Weight: 277.17
• EINECS: -0
• Product Categories: API intermediates;Asymmetric Synthesis;B (Classes of Boron Compounds);B-Bromocatecholborane, etc.;Synthetic Organic Chemistry;Asymmetric Synthesis;Chiral Catalysts, Ligands, and Reagents;Reduction;organic or inorganic borate
• Mol File: 112022-81-8.mol
• Article Data: 17

Chemical Properties

• Melting Point: 115-117°C
• Boiling Point: 111 °C
• Flash Point: 40 °F
• Appearance: Colorless to amber/Liquid
• Density: 0.93 g/mL at 20 °C(lit.)
• Vapor Pressure: 6.7E-06mmHg at 25°C
• Refractive Index: -68 ° (C=1, MeOH)
• Storage Temp.: Refrigerator
• PKA: 1.02±0.40(Predicted)
• Water Solubility: Hydrolyzes in water.
• Sensitive: Air & Moisture Sensitive
• BRN: 8492123
• CAS DataBase Reference: (S)-3,3-Diphenyl-1-methylpyrrolidino[1,2-c]-1,3,2-oxazaborole(CAS DataBase Reference)
• NIST Chemistry Reference: (S)-3,3-Diphenyl-1-methylpyrrolidino[1,2-c]-1,3,2-oxazaborole(112022-81-8)
• EPA Substance Registry System: (S)-3,3-Diphenyl-1-methylpyrrolidino[1,2-c]-1,3,2-oxazaborole(112022-81-8)

Safety Data

• Hazard Codes: Xi,Xn,F
• Statements: 36/37/38-67-65-63-48/20-11-19-40
• Safety Statements: 26-62-36/37-33-29-16
• RIDADR: UN 1294 3/PG 2
• WGK Germany: 3
• F: 10-21
• HazardClass: 3
• PackingGroup: II
• Hazardous Substances Data: 112022-81-8(Hazardous Substances Data)

Usage

Reaction

Convenient catalyst for the enantioselective borane reduction of ketones at ambient temperatures. Asymmetric synthesis of α-chiral hydroxyalkylphosphines via a catalytic, enantioselective reduction of acylphosphines. Nickel-catalyzed cross-couplings of benzylic pivalates with arylboroxines: Stereospecific formation of diarylalkanes and triarylmethanes. Enantioselective reduction of prochiral ketones with NaBH4/Me2SO4/(S)-Me-CBS.

Chemical Properties

Colorless to yellow liquid

Uses

Different sources of media describe the Uses of 112022-81-8 differently. You can refer to the following data:
1. (S)-2-Methyl-CBS-oxazaborolidine is used as an oxazaborolidine catalyst. It is also employed in the asymmetric reduction of prochiral ketones. Other applications include the enantioselective synthesis of α-hydroxy acids, α-amino acids, C2-symmetrical ferrocenyl diols and propargyl alcohols. It is an anhydrous catalyst for 'CBS' reduction reaction.
2. suzuki reaction

InChI:InChI=1/C18H20BNO/c1-19-20-14-8-13-17(20)18(21-19,15-9-4-2-5-10-15)16-11-6-3-7-12-16/h2-7,9-12,17H,8,13-14H2,1H3/t17-/m0/s1

Synthetic route

methylbis(diisopropylamino)borane (151293-60-6) + (R)-α,α-diphenylprolinol (22348-32-9) → (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8)

Conditions	Yield
In tetrahydrofuran; toluene reflux for 30 min; solvents are removed;	89%

(S)-diphenylprolinol (22348-32-9, 63401-04-7, 112022-88-5, 112068-01-6) + methylboronic acid → (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8)

Conditions	Yield
In toluene byproducts: H2O; refluxing of pyrrolidine deriv. and methylboronic acid in toluene for 3 h; evapn. of solvent in vac.;	86%
With 4 A molecular sieve In toluene byproducts: H2O; react. of pyrrolidine deriv. and methylboronic acid in toluene at 23°C in presence of molecular sieves within 1,5 h; evapn. of solvent in vac.;	86%

dihydroxy-methyl-borane (13061-96-6) + (R)-α,α-diphenylprolinol (22348-32-9) → (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8)

Conditions	Yield
In n-heptane at 40℃; Solvent; Temperature; Inert atmosphere; Reflux; Large scale;	83%

(S)-diphenylprolinol (22348-32-9, 63401-04-7, 112022-88-5, 112068-01-6) + dihydroxy-methyl-borane (13061-96-6) → (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8)

Conditions	Yield
In toluene for 3h; Heating;
With 4 A molecular sieve In toluene for 15h; Heating;
In toluene for 14h; Cyclization; Heating;

(S)-diphenylprolinol (22348-32-9, 63401-04-7, 112022-88-5, 112068-01-6) + Trimethylboroxine (823-96-1) → (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8)

Conditions	Yield
In toluene at 20℃; for 0.6h;
In toluene
In toluene at 20 - 155℃;

C22H30BNO2 + methyldi-n-butoxyborane (86595-28-0) → (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) + butan-1-ol (71-36-3)

Conditions	Yield
In toluene for 4h; Heating / reflux;

6-phenylsulfanyl-3,4-dihydro-2H-naphthalen-1-one (149915-80-0) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (R)-6-phenylsulfanyl-1,2,3,4-tetrahydro-naphthalen-1-ol (895534-20-0)

Conditions	Yield
Stage #1: 6-phenylsulfanyl-3,4-dihydro-2H-naphthalen-1-one; (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole With borane N,N-diethylaniline complex In toluene at 30 - 32℃; for 3h; Stage #2: With hydrogenchloride; methanol; water In toluene for 0.666667h;	98%

(S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) + 2,2,2-trifluoro-1-(1,1'-biphenyl-2-yl)ethanone (302912-29-4) → 1-([1,1'-biphenyl]-2-yl)-2,2,2-trifluoroethan-1-ol (945978-45-0)

Conditions	Yield
With hydrogenchloride In tetrahydrofuran; toluene	96%
With hydrogenchloride In tetrahydrofuran; toluene	96%

dimethyl sulfide borane (13292-87-0) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (3aS)-1-methyl-3, 3-diphenyl-tetrahydro-pyrrolo[1,2-c][1,3,2]oxazaborole borane complex

Conditions	Yield
In toluene vac. transferring of toluene onto (S)-2-methyl-CBS-oxazaborolidine; addn. of BH3*SMe2 by syringe at -78°C; stirring at room temp. for 2 hand then at -10°C for 5 h; vac. transferring of pentane; pptn., filtration, washing with pentane; removal of volatiles in vac., drying overnight;	91%

BH3.S(CH3)2 + (S)-oxazaborolidine + diethyl ether (60-29-7) + 2-pentyl-2-cyclopenten-1-one (25564-22-1) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (+)-(1R)-2-pentyl-1-cyclopenten-1-ol + (R)-2-pentyl-2-cyclopentenol (202530-97-0)

Conditions	Yield
With hydrogenchloride In tetrahydrofuran; methanol; toluene	A n/a B 89%

Sn(C4H9)3(CH3)2C3HO (160539-64-0) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → Sn(C4H9)3(CH3)2C3H2(OH)

Conditions	Yield
With benzo[1,3,2]dioxaborole In toluene -30°C to -20°C;	85%

C20H16O7 + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → C20H18O7

Conditions	Yield
Stage #1: (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole With dimethylsulfide borane complex In tetrahydrofuran; toluene at 0℃; for 0.25h; Stage #2: C20H16O7 In tetrahydrofuran at -78 - 20℃; for 1h; stereoselective reaction;	85%

(S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (S)-diphenylprolinol (22348-32-9, 63401-04-7, 112022-88-5, 112068-01-6)

Conditions	Yield
With water	77%

3-Nitroacetophenone (121-89-1) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (R)-1-(3-nitrophenyl)ethanol (76116-24-0)

Conditions	Yield
Stage #1: (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole With borane Ν,Ν-diethylaniline complex In toluene at 30℃; for 0.333333h; Inert atmosphere; Stage #2: 3-Nitroacetophenone In toluene at 30℃; for 5.5h;	74%

1-(3-Bromophenyl)ethanone (2142-63-4) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (R)-1-(3-bromophenyl)ethanol (52780-14-0, 64382-14-5, 134615-22-8, 134615-24-0)

Conditions	Yield
With dimethyl sulfide borane In tetrahydrofuran; toluene at 30℃; for 7h;	54%

borane-THF + 3-(2-bromoacetyl)pyridine hydrobromide (17694-68-7) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (1R)-2-bromo-1-(3-pyridinyl)-1-ethanol (391906-07-3)

Conditions	Yield
In tetrahydrofuran; methanol	34%
In tetrahydrofuran; methanol	27%

2-Chloro-4'-fluoroacetophenone (456-04-2) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → 4-fluorostyrene oxide (18511-62-1, 53631-23-5, 134356-73-3, 134356-74-4)

Conditions	Yield
With sodium hydroxide In tetrahydrofuran

aqueous potassium carbonate + di-tert-butyl dicarbonate (24424-99-5) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → [3-Hydroxy-3-(3-pyridinyl)propyl]carbamic acid, 1,1-dimethylethyl ester (357405-01-7)

Conditions	Yield
With hydrogenchloride; borane In tetrahydrofuran; methanol; toluene	928 mg (73%)

(S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) + 4-chloro-1-(4-methylphenyl)butan-1-one (38425-26-2) → R-α-(3-Chloropropyl)-4-methyl-benzenemethanol (357443-51-7)

Conditions	Yield
In tetrahydrofuran; methanol

{1-[4-(6-Methoxy-pyridin-3-yl)-2-oxo-but-3-enyl]-5(R)-methyl-2-oxo-pyrrolidin-3(S)-yl}-carbamic Acid Tert-butyl Ester + dimethyl sulfide borane (13292-87-0) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → {1-[2(R)-Hydroxy-4-(6-methoxy-pyridin-3-yl)-but-3-enyl]-5(R)-methyl-2-oxo-pyrrolidin-3(S)-yl }-carbamic Acid Tert-butyl Ester

Conditions	Yield
In tetrahydrofuran; methanol; dichloromethane; toluene

{1-[4-(2-methyl-pyrimidin-5-yl)-2-oxo-but-3-enyl]-5(R)-methyl-2-oxo-pyrrolidin-3(S)-yl}-carbamic Acid Tert-butyl Ester + dimethyl sulfide borane (13292-87-0) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → {1-[2-Hydroxy-4-(2-methyl-pyrimidin-5-yl)-but-3-enyl]-5(R)-methyl-2-oxo-pyrrolidin-3(S)-yl}-carbamic Acid Tert-butyl Ester

Conditions	Yield
In tetrahydrofuran; methanol; dichloromethane; toluene

borane-THF + 2,4-dichlorophenacyl bromide (2631-72-3) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (S)-2-bromo-1-(2,4-dichlorophenyl)ethan-1-ol (187164-20-1)

Conditions	Yield
In tetrahydrofuran; methanol

(S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) + 5-[3-[4-(4-fluorophenyl)piperazin-1-yl]propyl]-1-methyl-1,4,5,6,7,8-hexahydropyrrolo[3,2-c]azepine-4,8-dione (191591-86-3) → (+)-5-[3-[4-(4-fluorophenyl)piperazin-1-yl]propyl]-8-hydroxy-1-methyl-1,4,5,6,7,8-hexahydropyrrolo[3,2-c]azepin-4-one

Conditions	Yield
In toluene

(E)-(phenylsulfinyl)but-3-en-2-one (33944-98-8) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (R,E)-4-phenylthio-3-buten-2-ol

2,2,2-trifluoro-1-(4-fluorophenyl)ethanone (655-32-3) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → 2,2,2-trifluoro-1-(4-fluorophenyl)ethanol (17556-41-1, 50562-19-1, 131832-02-5)

Conditions	Yield
With benzo[1,3,2]dioxaborole In dichloromethane at -78℃;	n/a

borane (13283-31-3) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → N(CH2)3CHC(C6H5)2OBCH3(BH3) (461412-21-5, 112022-90-9, 545435-36-7, 452935-20-5, 170081-63-7, 415914-26-0)

Conditions	Yield
In tetrahydrofuran react. of oxazaborolidine deriv. and BH3 in soln.; not isolated;

isopropyl 7-{(4R)-4-[(1E)-4,4-difluoro-3-oxo-4-phenylbut-1-en-1-yl]-2-oxo-1,3-oxazinan-3-yl}heptanoate (768400-09-5) + isopropyl 7-[(4R)-4-formyl-2-oxo-1,3-oxazinan-3-yl]heptanoate (768400-08-4) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → isopropyl 7-{(4R)-4-[(1E)-4,4-difluoro-3-hydroxy-4-phenylbut-1-en-yl]-2-oxo-1,3-oxanzinan-3-yl}heptanoate

Conditions	Yield
Stage #1: isopropyl 7-{(4R)-4-[(1E)-4,4-difluoro-3-oxo-4-phenylbut-1-en-1-yl]-2-oxo-1,3-oxazinan-3-yl}heptanoate; (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole With benzo[1,3,2]dioxaborole In toluene at -78℃; for 1h; Stage #2: isopropyl 7-[(4R)-4-formyl-2-oxo-1,3-oxazinan-3-yl]heptanoate In toluene at -78℃; for 1h; Stage #3: With hydrogenchloride In water; toluene

(S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → (S)-methyloxazaborolidine

Conditions	Yield
With dimethylsulfide borane complex In toluene at 20℃; for 0.5h;

1-(4′-fluoro[1,1′-biphenyl]-2-yl)ethan-1-one (552885-75-3) + (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole (112022-81-8) → C14H13FO + C14H13FO

Conditions	Yield
Stage #1: (S)-1-methyl-3,3-diphenyl-hexahydropyrrolo[1,2-c][1,3,2]oxazaborole With borane-THF In tetrahydrofuran at -30℃; for 1h; Inert atmosphere; Stage #2: 1-(4′-fluoro[1,1′-biphenyl]-2-yl)ethan-1-one In tetrahydrofuran at -30℃; for 1h; Overall yield = 86 %; Overall yield = 1.8 g;	A n/a B n/a

Upstream product

• 13061-96-6 dihydroxy-methyl-borane 
• 22348-32-9 (R)-α,α-diphenylprolinol 
• 151293-60-6 methylbis(diisopropylamino)borane 
• 22348-32-9 (S)-diphenylprolinol 
• 86595-28-0 methyldi-n-butoxyborane 
• 823-96-1 Trimethylboroxine 

Downstream Products

• 202530-97-0 (R)-2-pentyl-2-cyclopentenol 
• 17556-41-1 2,2,2-trifluoro-1-(4-fluorophenyl)ethanol 
• 461412-21-5 N(CH₂)3CHC(C₆H₅)2OBCH₃(BH₃) 
• 22348-32-9 (S)-diphenylprolinol 
• 1354227-36-3 C₁₀H₂₁NO₃ 
• 52780-14-0 (R)-1-(3-bromophenyl)ethanol 
• 76116-24-0 (R)-1-(3-nitrophenyl)ethanol 
• 191592-36-6 (+)-5-[3-[4-(4-fluorophenyl)piperazin-1-yl]propyl]-8-hydroxy-1-methyl-1,4,5,6,7,8-hexahydropyrrolo[3,2-c]azepin-4-one 
• 187164-20-1 (S)-2-bromo-1-(2,4-dichlorophenyl)ethan-1-ol 
• 391906-07-3 (1R)-2-bromo-1-(3-pyridinyl)-1-ethanol 
• 357443-51-7 R-α-(3-Chloropropyl)-4-methyl-benzenemethanol 
• 18511-62-1 4-fluorostyrene oxide 
• 895534-20-0 (R)-6-phenylsulfanyl-1,2,3,4-tetrahydro-naphthalen-1-ol 

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