26 research outputs found
Palladium-Catalyzed Three-Component Cross-Coupling of Conjugated Dienes with Indoles Using Ethynylbenziodazolones as Electrophilic Alkynylating Reagents
A palladium-catalyzed regioselective 1,2-alkynyl-carbonalization
of conjugated dienes with ethynylbenziodazolone (EBZ) and indoles
has been developed for the first time. Various molecules containing
alkenyl, alkynyl, and indole groups were readily obtained. Moreover,
the resulting products can be applied to various derivatizations.
This protocol uses EBZ as an electrophilic alkynylating reagent, avoiding
the byproduct of dimerization of alkynes
Catalytic Enantioselective Intermolecular Three-Component Sulfenylative Difunctionalizations of 1,3-Dienes
This work demonstrates regio- and enantioselective intermolecular
three-component oxysulfenylations of 1,3-dienes with alcohols, phenols,
acids, and water as O-nucleophiles. These reactions
were enabled by the cooperative catalysis of chiral sulfide and phosphoric
acid. Various useful sulfur-containing allylic ethers, allylic esters,
and allylic alcohols were readily obtained in moderate to excellent
yields with high to excellent enantioselectivities and excellent regioselectivities.
This protocol provides high chemo-, regio-, and enantioselectivities
together with a broad scope and good functional group compatibility
Catalytic Enantioselective Intermolecular Three-Component Sulfenylative Difunctionalizations of 1,3-Dienes
This work demonstrates regio- and enantioselective intermolecular
three-component oxysulfenylations of 1,3-dienes with alcohols, phenols,
acids, and water as O-nucleophiles. These reactions
were enabled by the cooperative catalysis of chiral sulfide and phosphoric
acid. Various useful sulfur-containing allylic ethers, allylic esters,
and allylic alcohols were readily obtained in moderate to excellent
yields with high to excellent enantioselectivities and excellent regioselectivities.
This protocol provides high chemo-, regio-, and enantioselectivities
together with a broad scope and good functional group compatibility
Total Synthesis of (±)-Maistemonine, (±)-Stemonamide, and (±)-Isomaistemonine
A full account of the total synthesis of (±)-maistemonine,
(±)-stemonamide, and (±)-isomaistemonine is presented. Two
approaches have been developed to construct the basic pyrrolo[1,2-a]azepine core of the Stemona alkaloids,
featuring a tandem semipinacol/Schmidt rearrangement of a secondary
azide and a highly stereoselectively desymmetrizing intramolecular
Schmidt reaction, respectively. To build the common spiro-γ-butyrolactone,
a new protocol was carried out by utilizing an intramolecular ketone-ester
condensation as the key transformation. The vicinal butyrolactone
moiety of (±)-maistemonine was stereoselectively introduced via
a one-pot procedure involving the epimerization at C-3 and carbonyl
allylation/lactonization. Moreover, (±)-stemonamide was divergently
synthesized from a common intermediate, and (±)-isomaistemonine
was obtained via the epimerization of (±)-maistemonine at C-12
Total Synthesis of (±)-Maistemonine, (±)-Stemonamide, and (±)-Isomaistemonine
A full account of the total synthesis of (±)-maistemonine,
(±)-stemonamide, and (±)-isomaistemonine is presented. Two
approaches have been developed to construct the basic pyrrolo[1,2-a]azepine core of the Stemona alkaloids,
featuring a tandem semipinacol/Schmidt rearrangement of a secondary
azide and a highly stereoselectively desymmetrizing intramolecular
Schmidt reaction, respectively. To build the common spiro-γ-butyrolactone,
a new protocol was carried out by utilizing an intramolecular ketone-ester
condensation as the key transformation. The vicinal butyrolactone
moiety of (±)-maistemonine was stereoselectively introduced via
a one-pot procedure involving the epimerization at C-3 and carbonyl
allylation/lactonization. Moreover, (±)-stemonamide was divergently
synthesized from a common intermediate, and (±)-isomaistemonine
was obtained via the epimerization of (±)-maistemonine at C-12
Total Synthesis of (±)-Maistemonine, (±)-Stemonamide, and (±)-Isomaistemonine
A full account of the total synthesis of (±)-maistemonine,
(±)-stemonamide, and (±)-isomaistemonine is presented. Two
approaches have been developed to construct the basic pyrrolo[1,2-a]azepine core of the Stemona alkaloids,
featuring a tandem semipinacol/Schmidt rearrangement of a secondary
azide and a highly stereoselectively desymmetrizing intramolecular
Schmidt reaction, respectively. To build the common spiro-γ-butyrolactone,
a new protocol was carried out by utilizing an intramolecular ketone-ester
condensation as the key transformation. The vicinal butyrolactone
moiety of (±)-maistemonine was stereoselectively introduced via
a one-pot procedure involving the epimerization at C-3 and carbonyl
allylation/lactonization. Moreover, (±)-stemonamide was divergently
synthesized from a common intermediate, and (±)-isomaistemonine
was obtained via the epimerization of (±)-maistemonine at C-12
Total Synthesis of (±)-Maistemonine, (±)-Stemonamide, and (±)-Isomaistemonine
A full account of the total synthesis of (±)-maistemonine,
(±)-stemonamide, and (±)-isomaistemonine is presented. Two
approaches have been developed to construct the basic pyrrolo[1,2-a]azepine core of the Stemona alkaloids,
featuring a tandem semipinacol/Schmidt rearrangement of a secondary
azide and a highly stereoselectively desymmetrizing intramolecular
Schmidt reaction, respectively. To build the common spiro-γ-butyrolactone,
a new protocol was carried out by utilizing an intramolecular ketone-ester
condensation as the key transformation. The vicinal butyrolactone
moiety of (±)-maistemonine was stereoselectively introduced via
a one-pot procedure involving the epimerization at C-3 and carbonyl
allylation/lactonization. Moreover, (±)-stemonamide was divergently
synthesized from a common intermediate, and (±)-isomaistemonine
was obtained via the epimerization of (±)-maistemonine at C-12
Total Synthesis of (±)-Maistemonine, (±)-Stemonamide, and (±)-Isomaistemonine
A full account of the total synthesis of (±)-maistemonine,
(±)-stemonamide, and (±)-isomaistemonine is presented. Two
approaches have been developed to construct the basic pyrrolo[1,2-a]azepine core of the Stemona alkaloids,
featuring a tandem semipinacol/Schmidt rearrangement of a secondary
azide and a highly stereoselectively desymmetrizing intramolecular
Schmidt reaction, respectively. To build the common spiro-γ-butyrolactone,
a new protocol was carried out by utilizing an intramolecular ketone-ester
condensation as the key transformation. The vicinal butyrolactone
moiety of (±)-maistemonine was stereoselectively introduced via
a one-pot procedure involving the epimerization at C-3 and carbonyl
allylation/lactonization. Moreover, (±)-stemonamide was divergently
synthesized from a common intermediate, and (±)-isomaistemonine
was obtained via the epimerization of (±)-maistemonine at C-12
Total Synthesis of (±)-Maistemonine, (±)-Stemonamide, and (±)-Isomaistemonine
A full account of the total synthesis of (±)-maistemonine,
(±)-stemonamide, and (±)-isomaistemonine is presented. Two
approaches have been developed to construct the basic pyrrolo[1,2-a]azepine core of the Stemona alkaloids,
featuring a tandem semipinacol/Schmidt rearrangement of a secondary
azide and a highly stereoselectively desymmetrizing intramolecular
Schmidt reaction, respectively. To build the common spiro-γ-butyrolactone,
a new protocol was carried out by utilizing an intramolecular ketone-ester
condensation as the key transformation. The vicinal butyrolactone
moiety of (±)-maistemonine was stereoselectively introduced via
a one-pot procedure involving the epimerization at C-3 and carbonyl
allylation/lactonization. Moreover, (±)-stemonamide was divergently
synthesized from a common intermediate, and (±)-isomaistemonine
was obtained via the epimerization of (±)-maistemonine at C-12
Total Synthesis of (±)-Maistemonine, (±)-Stemonamide, and (±)-Isomaistemonine
A full account of the total synthesis of (±)-maistemonine,
(±)-stemonamide, and (±)-isomaistemonine is presented. Two
approaches have been developed to construct the basic pyrrolo[1,2-a]azepine core of the Stemona alkaloids,
featuring a tandem semipinacol/Schmidt rearrangement of a secondary
azide and a highly stereoselectively desymmetrizing intramolecular
Schmidt reaction, respectively. To build the common spiro-γ-butyrolactone,
a new protocol was carried out by utilizing an intramolecular ketone-ester
condensation as the key transformation. The vicinal butyrolactone
moiety of (±)-maistemonine was stereoselectively introduced via
a one-pot procedure involving the epimerization at C-3 and carbonyl
allylation/lactonization. Moreover, (±)-stemonamide was divergently
synthesized from a common intermediate, and (±)-isomaistemonine
was obtained via the epimerization of (±)-maistemonine at C-12