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

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

Uses

Used in Asymmetric Reduction:
(S)-3,3-Diphenyl-1-methylpyrrolidino[1,2-c]-1,3,2-oxazaborole is used as an oxazaborolidine catalyst for the asymmetric reduction of prochiral ketones. This application is significant in the synthesis of enantiomerically pure compounds, which are crucial in the pharmaceutical industry for the development of drugs with fewer side effects.
Used in Enantioselective Synthesis:
(S)-3,3-Diphenyl-1-methylpyrrolidino[1,2-c]-1,3,2-oxazaborole is also utilized in the enantioselective synthesis of various chiral molecules, such as α-hydroxy acids, α-amino acids, C2-symmetrical ferrocenyl diols, and propargyl alcohols. The enantioselective synthesis is essential for creating biologically active molecules with specific properties, which are vital in the fields of pharmaceuticals, agrochemicals, and materials science.
Used in Suzuki Reaction:
(S)-3,3-Diphenyl-1-methylpyrrolidino[1,2-c]-1,3,2-oxazaborole is employed in the Suzuki reaction, a widely used cross-coupling reaction in organic chemistry. This reaction allows the formation of carbon-carbon bonds, which are fundamental in the construction of complex molecular structures. The use of this compound as a catalyst in the Suzuki reaction contributes to the development of new synthetic routes and the production of advanced materials and pharmaceuticals.

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.

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

• 17556-41-1 2,2,2-trifluoro-1-(4-fluorophenyl)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 
• 202530-97-0 (R)-2-pentyl-2-cyclopentenol 
• 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 
• 1354227-36-3 C₁₀H₂₁NO₃ 
• 52780-14-0 (R)-1-(3-bromophenyl)ethanol 
• 76116-24-0 (R)-1-(3-nitrophenyl)ethanol 
• 22348-32-9 (S)-diphenylprolinol 
• 461412-21-5 N(CH₂)3CHC(C₆H₅)2OBCH₃(BH₃) 

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We derived a novel equation capable of predicting the degree of enantioselectivity in a catalytic reaction without any knowledge of the reaction mechanism and/or the transition-state structure, and tested the validity of this equation by changing substrates systematically in the lipase or oxazaborolidine-catalyzed reactions. A good correlation was observed between the predicted and observed E values, and the stereochemistry of the products could be predicted correctly in most cases (28 out of 30).

Total synthesis of (+)-azaspiracid-1. An exhibition of the intricacies of complex molecule synthesis

The synthesis of the marine neurotoxin azaspiracid-1 has been accomplished. The individual fragments were synthesized by catalytic enantioselective processes: A hetero-Diels-Alder reaction to afford the E- and HI-ring fragments, a carbonyl-ene reaction to furnish the CD-ring fragment, and a Mukaiyama aldol reaction to deliver the FG-ring fragment. The subsequent fragment couplings were accomplished by aldol and sulfone anion methodologies. All ketalization events to form the nonacyclic target were accomplished under equilibrating conditions utilizing the imbedded configurations of the molecule to adopt one favored conformation. A final fragment coupling of the anomeric EFGHI-sulfone anion to the ABCD-aldehyde completed the convergent synthesis of (+)-azaspiracid-1.

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.

1-AMIDO-4-PHENYL-4-BENZYLOXYMETHYL-PIPERIDINE DERIVATIVES AND RELATED COMPOUNDS AS NEUROKININ-1(NK-1) ANTAGONISTS FOR THE TREATMENT OF EMESIS, DEPRESSION, ANXIETY AND COUGH

Disclosed are NK1 antagonists having the formula: Also disclosed are uses of compounds of formula (I) for the manufacture of a medicament for treating a number of physiological disorders, symptoms or diseases, including emesis, depression, anxiety and cough.