Solvent-Free Methallylboration of Ketones Accelerated by <i>tert</i>-Alcohols

A solvent- and metal-free process has been developed for the direct methallylboration of ketones employing the stable <i>B</i>-methallylborinane <b>1</b>, which was accelerated by tertiary alcohols. In the presence of 2.0 equiv of readily available tertiary alcohols such as <i>tert</i>-amyl alcohol, the methallylation products were prepared at room temperature in excellent yields. The salient features of the described process include simple operation, high efficiency, and mild reaction conditions

One-Pot and Regiospecific Synthesis of 2,3-Disubstituted Indoles from 2‑Bromoanilides via Consecutive Palladium-Catalyzed Sonogashira Coupling, Amidopalladation, and Reductive Elimination

A practical one-pot and regiospecific three-component process for the synthesis of 2,3-disubstituted indoles from 2-bromoanilides was developed via consecutive palladium-catalyzed Sonogashira coupling, amidopalladation, and reductive elimination

Asymmetric Synthesis of Sulfinamides Using (−)-Quinine as Chiral Auxiliary

A process has been designed and demonstrated for the asymmetric synthesis of sulfinamides using quinine as auxiliary. A variety of chiral sulfinamides including <i>N</i>-alkyl sulfinamides with diverse structure were prepared in good yields and excellent enantioselectivity starting from easily available and inexpensive reagents. The auxiliary quinine could be recovered and recycled

An Enantioselective Synthesis of an 11-β-HSD‑1 Inhibitor via an Asymmetric Methallylation Catalyzed by (<i>S</i>)‑3,3′‑F₂‑BINOL

An efficient asymmetric synthesis of 11-β-HSD inhibitor <b>1</b> has been accomplished in five linear steps and 53% overall yield, starting from the readily available 3-chloro-1-phenylpropan-1-one. The key feature of the synthesis includes an asymmetric methallylation of 3-chloro-1-phenylpropan-1-one catalyzed by the highly effective organocatalyst (<i>S</i>)-3,3′-F₂-BINOL under solvent-free and metal-free conditions

Asymmetric Methallylation of Ketones Catalyzed by a Highly Active Organocatalyst 3,3′‑F₂‑BINOL

(<i>S</i>)-3,3′-F₂-BINOL has been synthesized for the first time and demonstrated as a highly active organocatalyst for asymmetric methallylation of ketones. Up to 98:2 enantioselectivity and 99% yield were obtained with 5 mol % catalyst loading. The catalyst (<i>S</i>)-3,3′-F₂-BINOL could be easily recovered and reused

Efficient Asymmetric Synthesis of <i>P</i>‑Chiral Phosphine Oxides via Properly Designed and Activated Benzoxazaphosphinine-2-oxide Agents

A general, efficient, and highly diastereoselective method for the synthesis of structurally and sterically diverse <i>P</i>-chiral phosphine oxides was developed. The method relies on sequential nucleophilic substitution on the versatile chiral phosphinyl transfer agent 1,3,2-benzoxazaphosphinine-2-oxide, which features enhanced and differentiated P–N and P–O bond reactivity toward nucleophiles. The reactivities of both bonds are fine-tuned to allow cleavage to occur even with sterically hindered nucleophiles under mild conditions

A Highly Concise and Convergent Synthesis of HCV Polymerase Inhibitor Deleobuvir (BI 207127): Application of a One-Pot Borylation–Suzuki Coupling Reaction

A highly concise and convergent synthesis of HCV polymerase inhibitor Deleobuvir (BI 207127, <b>1</b>) was achieved, featuring efficient Pd-catalyzed one-pot borylation–Suzuki coupling where TFP was identified as the unique ligand effective for these transformations

Development of a Scalable, Chromatography-Free Synthesis of <i>t</i>‑Bu-SMS-Phos and Application to the Synthesis of an Important Chiral CF₃‑Alcohol Derivative with High Enantioselectivity Using Rh-Catalyzed Asymmetric Hydrogenation

A chromatography-free, asymmetric synthesis of the C2-symmetric P-chiral diphosphine <i>t</i>-Bu-SMS-Phos was developed using a chiral auxiliary-based approach in five steps from the chiral auxiliary in 36% overall yield. Separtion and recovery of the auxiliary were achieved with good yield (97%) to enable recycling of the chiral auxiliary. An air-stable crystalline form of the final ligand was identified to enable isolation of the final ligand by crystallization to avoid chromatography. This synthetic route was applied to prepare up to 4 kg of the final ligand. The utility of this material was demonstrated in the asymmetric hydrogenation of trifluoromethyl vinyl acetate at 0.1 mol % Rh loading to access a surrogate for the pharmaceutically relavent chiral trifluoroisopropanol fragment in excellent yield and enantiomeric excess (98.6%)