6030-70-2

Upstream product

• 516-95-0 epicholestanol 
• 98-88-4 benzoyl chloride 
• 80-97-7 Cholestanol 
• 65-85-0 benzoic acid 
• 582-25-2 Potassium benzoate 
• 3381-51-9 (3S,5S,8R,9S,10S,13R,14S,17R)-10,13-dimethyl-17-((R)-6-methylheptan-2-yl)hexadecahydro-1H-cyclopenta[a]phenanthren-3-yl methanesulfonate 
• 80-97-7 3-β-cholestanol 
• 566-88-1 dihydrocholesterone 
• 165452-00-6 Dithiocarbonic acid O-[(3S,5S,8R,9S,10S,13R,14S,17R)-17-((R)-1,5-dimethyl-hexyl)-10,13-dimethyl-hexadecahydro-cyclopenta[a]phenanthren-3-yl] ester S-prop-2-ynyl ester 

Relevant academic research and scientific papers

Inversion of secondary chiral alcohols in toluene with the tunable complex of R3N{single bond}R′COOH

The SN2 reaction of enantiomerically pure sulfonates with the tunable complex of R3N-R′COOH in toluene has been extensively studied. It was revealed that the molar ratio of the tertiary amines and carboxylic acids in the complex of R3NR′COOH is crucial for the SN2 reaction, and should be tuned for each sulfonate to give the best yield. Fifteen sulfonates 1 and 3-13 (Scheme 2) were prepared and transformed into 22 corresponding inverted esters 2 and 14-24 (Scheme 2) in good to high yields.

13C NMR spectral assignment of five epimeric 3α- versus 3β-functionalized cholestane pairs

13C NMR chemical shift assignments of five α- and β-epimeric pairs of cholestanes functionalized at C-3 are presented. Empirical increment estimations proved to be a valuable tool for the unequivocal structural elucidation when compared with th

Nucleophilic Substitution Reactions of (Alkoxymethylene)dimethylammonium Chloride

The use of imidate esters as potential replacements for diethyl azodicarboxylate and triphenylphosphine in the Mitsunobu reaction is described. A series of secondary alcohols were allowed to react with (chloromethylene)dimethylammonium chloride, generated from dimethylformamide (DMF) and oxalyl chloride, to give imidate esters. Reaction of these salts with potassium benzoate or potassium phthalimide gave the products of SN2 substitution in excellent yields with clean inversion of stereochemistry. Optimization of reaction conditions is discussed as a means to increase the atom economy of the process by minimizing the quantity of nucleophile required.

Mitsunobu acylation of sterically congested secondary alcohols by N,N, N′,N′-tetramethylazodicarboxamide-tributylphosphine reagents

Four secondary alcohols of different steric environment reacted with five carboxylic acids of different acidity in the presence of N,N,N′,N′-tetramethylazodicarboxamide and tributylphosphine to give the corresponding epi-esters in better yield than with diethyl azodicarboxylate-triphenylphosphine in most cases. Of special merit is the combination of the new reagent system with p-methoxybenzoic acid to achieve complete inversion of sterically congested secondary alcohols.

Nucleophilic Substitution of (Alkoxymethylene)dimethylammonium Chloride with Carboxylate Salts: a Convenient Procedure for the Synthesis of Esters with Inversion of Configuration

Secondary alcohols are converted into benzoate esters with inversion of configuration via sequential reaction with (chloromethylene)dimethylammonium chloride and potassium benzoate.

1,1′-(azodicarbonyl)dipiperidine-tributylphosphine, a new reagent system for mitsunobu reaction

The 1,1′-(azodicarbonyl)dipiperidine (ADDP)-tributylphosphine (TBP) system was developed as a new institute of the Mitsunobu reagent. The new system activates nitrogen or carbon nucleophiles, known to be innert or poorly reactive with the Mitsunobu reagent, to react with alcohols satisfactorily forming C-N or C-C bonds. The inversion of stereogenic carbinyl carbons was confirmed in the acylaltion reaction of two sec-alcohols.

The Use of a Phosphine Containing a Basic Group in the Mitsunobu Esterification Reaction

Use of diphenyl(2-pyridyl)phosphine instead of triphenylphosphine in the Mitsunobu esterification reaction facilitates isolation of the desired ester.The resulting phosphine oxide is readily removed by a dilute acid wash. 31P n.m.r. investigations of the

Desorption Chemical Ionization Mass Spectrometry of Epimeric 3-Hydroxysteroids and Derivatives. Stereoselectivity and Nucleophilic Substitution with Ammonia

The desorption chemical ionization mass spectra, using ammonia as reagent gas, of several epimeric 3-hydroxysteroids and their ether and carboxylic acid ester derivatives are reported.In the case of steroids possessing a Δ4- or Δ5-3α-benzoate moiety, stereospecific stabilization of the protonated molecular ion + is observed.This behaviour is rationalized in terms of interaction of the double bond and the protonated benzoate group at C-3.Nucleophilic substitution by NH3 is observed when a double bond is present in the vicinity of the substitution center.The nature and the stereochemistry of the leaving group influence this substitution reaction.Our results seem to indicate the operation of a two-step mechanism (e.g.SN1 type reaction) rather than a SN2 type mechanism for the formation of the substitution ion +.

A High Yield Preparation of Phenyl Esters of Carboxylic Acids in the Presence of Diethyl Azodicarboxylate and Triphenylphosphine. Mechanistic Aspects of the Reaction

The reaction of phenols with carboxylic acids in the presence of diethyl azodicarboxylate and triphenylphosphine has been studied.Mechanistic aspects of the alkylation and acylation reactions with participation of quaternary phosphonium salts have been discussed.