51532-31-1

Upstream product

• 49642-47-9 methyl (R)-2-methylbutyric acid 
• 811-49-4 ethyllithium 
• 917-54-4 methyllithium 
• 53229-39-3 (3R)-(-)-1,2-Epoxy-3-methylhexan 
• 27771-19-3 (E)-4-methylhept-4-en-3-one 
• 75-24-1 trimethylaluminum 
• 106059-05-6 (4S,5S)-2-((E)-1-Ethyl-pent-1-enyl)-[1,3]dioxolane-4,5-dicarboxylic acid bis-dimethylamide 
• 14979-39-6 methyl-4 heptanol-3 threo 
• 77858-04-9 (1-Ethyl-propylidene)-((S)-1-methoxymethyl-2-phenyl-ethyl)-amine 
• 107-08-4 1-iodo-propane 
• 97-61-0 2-Methylpentanoic acid 
• 76695-82-4 (R)-ethyl 4-hydroxyhex-2-ynoate 
• 77075-70-8 (4R,5R)-5-Ethyl-4-methyl-tetrahydro-furan-2-ol 
• 77075-75-3 (3R,4R)-4-Methyl-hept-6-en-3-ol 

Downstream Products

• 1289377-51-0 C₂₂H₃₆O₄ 
• 1289377-52-1 C₂₂H₃₈O₄ 
• 1289377-53-2 C₃₄H₆₆O₄Si₂ 
• 1289377-58-7 C₂₅H₄₂O₄ 

Relevant academic research and scientific papers

Enantioselective cyclopropanation of carboxylic esters with alkyl magnesium bromides in the presence of titanium(IV) (4R,5R)-TADDOLates

The reaction of isopropyl 4-chlorobutyrate with 3 equiv of n-BuMgBr in the presence of 1 equiv of titanium(IV) (4R,5R)-TADDOLate in diethyl ether led to the formation of (1S,2S)-(3-chloropropyl)-2-ethylcyclopropanol in 55-70% yield and 55-65% ee. The reaction was performed in the presence of 20 mol % of the catalyst without significant loss in yield and enantioselectivity when solutions of the carboxylic ester and the Grignard reagent were added simultaneously at an equal rate to a refluxing solution of the titanium catalyst in ether. The cyclopropanation of isopropyl propionate under the same conditions gave (1S,2S)-1-ethyl-2-propylcyclopropanol in 50% yield and 65% ee. Its absolute configuration was determined by chemical correlation through acid-catalyzed isomerization to enantiomerically enriched (R)-(-)-4-methyl-3-heptanone, known as a minor component of the trail pheromone of ant Aphaenogaster albisetosus and enantiomer of the alarm pheromone of leaf-cutting ants Atta texana.

Formation, Alkylation, and Hydrolysis of Chiral Nonracemic N-Amino Cyclic Carbamate Hydrazones: An Approach to the Enantioselective α-Alkylation of Ketones

The α-alkylation of ketones is a fundamental synthetic transformation. The development of asymmetric variants of this reaction is important given that numerous natural products, drugs, and related compounds exist as α-functionalized ketones or derivatives thereof. We previously reported our preliminary studies on the development of a new enantioselective ketone α-alkylation procedure using N-amino cyclic carbamate (ACC) auxiliaries. In comparison to other auxiliary-based methods, ACC alkylation offers a number of advantages and is both highly enantioselective and high yielding. Herein, we provide a full account of our studies on the enantioselective ACC ketone α-alkylation method.

Investigating: Saccharomyces cerevisiae alkene reductase OYE 3 by substrate profiling, X-ray crystallography and computational methods

Saccharomyces cerevisiae OYE 3 shares 80% sequence identity with the well-studied Saccharomyces pastorianus OYE 1; however, wild-type OYE 3 shows different stereoselectivities toward some alkene substrates. Site-saturation mutagenesis of Trp 116 in OYE 3 followed by substrate profiling showed that the mutations had relatively little effect, opposite to that observed previously for OYE 1. The X-ray crystal structures of unliganded and phenol-bound OYE 3 were solved to 1.8 and 1.9 ? resolution, respectively. Both structures were nearly identical to that of OYE 1, with only a single amino acid difference in the active site region (Ser 296 versus Phe 296, part of loop 6). Despite their essentially identical static X-ray structures, molecular dynamics (MD) simulations revealed that loop 6 conformations differed significantly in solution between OYE 3 and OYE 1. In OYE 3, loop 6 remained nearly as open as observed in the crystal structure; by contrast, loop 6 closed over the active site of OYE 1 by ca. 4 ?. Loop closure likely generates a greater number of active site protein contacts for substrate bound to OYE 1 as compared to OYE 3. These differences provide an explanation for the differing stereoselectivities of OYE 3 and OYE 1, despite their nearly identical X-ray crystal structures.

One-pot multi-enzymatic synthesis of the four stereoisomers of 4-methylheptan-3-ol

The use of pheromones in the integrated pest management of insects is currently considered a sustainable and environmentally benign alternative to hazardous insecticides. 4-Methylheptan-3-ol is an interesting example of an insect pheromone, because its stereoisomers are active towards different species. All four possible stereoisomers of this compound were prepared from 4-methylhept-4-en-3-one by a one-pot procedure in which the two stereogenic centres were created during two sequential reductions catalysed by an ene-reductase (ER) and an alcohol dehydrogenase (ADH), respectively.

Total synthesis of hoiamide C

Chemical equations presented. Hoiamide C was synthesized in 16 steps with an overall yield of 1.8% starting from homoallylic alcohol 18, unambiguously confirming its structure.

ASYMMETRIC ALPHA FUNCTIONALIZATION AND ALPHA, ALPHA BISFUNCTIONALIZATION OF ALDEHYDES AND KETONES

The present invention relates, generally, to asymmetric α-functionalization and to asymmetric α,α-bisfunctionalization of ketones and aldehydes and, in particular, to chiral auxiliaries suitable for use in effecting such functionalizations and to methods

Simple and efficient asymmetric α-alkylation and α,α- bisalkylation of acyclic ketones by using chiral N-amino cyclic carbamate hydrazones

(Chemical Equation Presented) Distinguishing left from right: In the title reactions, chiral N-amino cyclic carbamates (ACCs) substantially diminish the drawbacks associated with the use of chiral dialkyl hydrazines, yet provide excellent stereoselectivity and high yields. In addition, ACCs exhibit a unique directing effect that overrides the inherent selectivity of lithium diisopropylamide (LDA) and enables the asymmetric α,α-bisalkylation of ketones (see scheme).

Enantiomeric partitioning using fluorous biphase methodology for lipase-mediated (trans)esterifications

Lipase-catalysed (trans)esterification reactions in homogenous perfluorocarbon-hydrocarbon solvents enabled direct enantiomeric partitioning (up to 95% ee) of the products by liquid-liquid separation.

A Conceptually Different Approach to the Asymmetric Synthesis of α-Substituted Carbonyl Compounds

A new approach has been demonstrated for the asymmetric synthesis of α-substituted carbonyl compounds.Thus, the key assymetric carbon-carbon bond formation is accomplished by the highly diastereoselective addition of organoaluminum reagents to the chiral α,β-unsaturated acetal derived from the α,β-unsaturated aldehyde and (R,R)-tartaric acid diamide to furnish the 1,4-adduct preferentially along with the 1,2-adduct as a minor product.Subsequent oxidation of the combined adducts with ozone or the system potassium permanganate/sodium periodate gives rise to the optically active α-substituted aldehyde, ketone, or carboxylic acid, respectively, with high enantioselectivities.The present method has been applied to the facile synthesis of an anti-inflammatory agent and the principal alarm pheromone of the leaf-cutting ant Atta texana in optically active forms.

ASYMMETRIC SYNTHESES VIA METALATED CHIRAL HYDRAZONESOVERALL ENANTIOSELECTIVE α-ALKYLATION OF ACYCLIC KETONES

A general method is described, which allows the overall enantioselective α-alkylation of acyclic ketones in good overall yields (44-86percent, 4 steps) and enantioselectivities ranging routinely from >94percent ee up to virtually complete asymmetric induction (99.5percent ee).The acyclic ketones are transformed to their corresponding "SAMP-hydrazones" (S)-2 by reaction with the enantiomerically pure hydrazine (S)-1-amino-2-methoxymethyl-pyrrolidine , readily available from (S)-proline.Metalation to form chiral azaenolates (S)-3 of ECCZCN-configuration and then alkylation to product hydrazones 4, followed by hydrazone cleavage via acidic hydrolysis of methiodides 9 in a two phase system or ozonolysis, leads to α-substituted, enantiomerically enriched, acyclic ketones 5.In special cases, where a phenyl group is directly attached to the newly generated center of chirality (5n,o,p), only low enantiomeric excesses are observed. 17 Examples, including first applications in natural product synthesis (cf 5a,b,e, and h) are summarized.