Targeted synthesis of 2,3-disubstituted 2-phospholenes using catalytic cycloalumination of acetylenes

Approach to the Synthesis of Five-Membered Organophosphorus Compounds via Alumoles and Alumolanes

“…It was established that, under the developed conditions, bisaluminacyclopentanes 9, obtained by the catalytic cycloalumination of 1,5-hexadiene, 1,7-octadiene, and 1,9-decadiene, react with phosphorus dihalides to form bisphospholanes 10 as a mixture of isomers with a total yield of 84-85% (Scheme 4) [14]. The reaction of substitution of the Al atom for the P atom in 4,5-disubstituted 2,3-dihydroalumoles was studied for the first time [16]. It was established that 4,5-disubstituted 2,3-dihydroalumoles 11, synthesized by the catalytic cycloaluminization of symmetrical acetylenes with AlEt3 under the action of a Cp2ZrCl2 catalyst, enter into the reaction of substitution of an aluminum atom for a phosphorus atom with phenyl-and alkyldichlorophosphines (~20 °C, 30 min) with the formation of 4,5-disubstituted 2,3-dihydrophospholes 12 in 84-92% yields (Scheme 5).…”

One‐pot Modification of Terpene's Methylenecyclobutane Derivatives

“…Subsequently, based on publications in , we attempted to replace the aluminum atom in compound 2 by selenium or phosphorus atom in order to obtain the corresponding selenophanes and phospholanes.…”

“…The reaction of OAC 2 with phenyldichlorophosphine taken in an equimolar amount with respect to Et 3 Al resulted in the synthesis of polycyclic phospholane, which was oxidized, due to its instability, without preliminary isolation by treatment with Н 2 О 2 to furnish 1,7,7‐trimethyl‐1″‐phenyldispiro[bicycle[2.2.1]heptane‐2,1′‐cyclobutane‐3′,3″‐phospholane]1″‐oxide 8 that gives the 1:1 mixture of syn and anti ‐isomers regarding the position of the phenyl substituent at phosphorus .…”

Catalytic Cycloalumination for the Synthesis of Norbornane-Annulated Phospholanes

“…The X-ray diffraction data for compound 4a are indicative of exo-annulation of phospholane and norbornane moieties in the molecule, which corresponds to the stereoconfiguration in the initial polycyclic aluminacyclopentane. 8 The phospholane ring occurs in the envelope conformation, as the P(3), C( 5), C (6), and C(2) atoms are coplanar to within 0.02 Å, while the C(4) atom deviates from the root-mean-square plane of these atoms by 0.714 Å. The pseudoequatorial orientation of the phenyl group was established considering the C(5)−C(4)−P(3)−C(1′) torsion angle, which is 148.64°(Figure 1).…”

“…Previously, , we demonstrated that simple five-membered aluminacarbocycles synthesized by catalytic cycloalumination of α-olefins and acetylenes with alkylhaloalanes in the presence of Zr- and Ti-based complex catalysts react with phosphorus dihalides to afford the corresponding five-membered OPCsphospholanesin high yields.…”