Untitled

Миронов, В. Ф.; Shtyrlina, A. A.; Коновалов, А. И.; Varaksina, E. N.; Azancheev, N. M.

doi:10.1023/a:1011354021443

Cited by 4 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Unlike tribromophospholes Xa and Xb, 2,2-dibromo-5-chloro-2-fluorobenzo[d] [1,3,2]dioxaphosphole (XVI) prepared from P(III) derivative XV reacts with phenyl-and p-tolylacetylene in a more complicated manner to give three benzophosphinines are formed, whose ratio slightly varies, depending on the concentration of the starting reagents. In any case, one of the products is preferred (53360%).…”

Section: äääääääääääämentioning

confidence: 99%

“…The signals are fairly well resolved, which allows the spectra to be assigned completely. The major product XVIIa contains no other substituents in the phenylene fragment than 7-Cl, which is easy to establish from the chemical shift of the C 7 signal (d C 137.69 ppm) and its muliplicity (d.d.d, 3 J HC 5 CC 7 12.9, 2 J HC 6 C 7 = 2 J HC 8 C 7 3.633.8 Hz). The multiplicity of the C 7 signal of compound …”

Section: äääääääääääämentioning

confidence: 99%

“…Hence, the possibility of the preferential formation of regioisomers of benzo[e] [1,2]oxaphosphinanes containing the chlorine atom para to the heteroring carbon atom, via the use of tribromophosphoranes like X and XVI that already have a halogen atom in the benzene ring, has been demonstrated for the first time This synthetic result is based, on the one side, on the weaker ability of the bromide anion, compared to chloride, to migrate into the benzo fragment of the benzophosphinine system in the course of reaction of P,P,P-tribromo-and P,P,P-trichlorobenzo[d] [1,3,2]dioxaphospholes with arylacetylenes and, on the other, on selective ipso substitution of the oxygen atom located para to the halogen atom that is already present in the benzo fragment of the starting phosphole.…”

Section: G Gmentioning

confidence: 99%

“…The reactions occur in mild conditions and involve formation of a phosphorus3carbon bond and phosphoryl group, as well as ipso-substitution of oxygen by carbon in the benzene ring. Depending on the nature of the alkyne, chlorine is regioselectively introduced para (with phenylacetylene) or ortho (with propargyl chloride) to the oxygen atom of the phosphinine ring [2,3]. 5 ]dioxaphosphole (IV) reacts with arylacetylenes to form benzophosphinines V and VI, the latter having no bromine in the benzene ring [1].…”

mentioning

confidence: 99%

See 3 more Smart Citations

Reaction of Trihalo(phenylenedioxy)phosphoranes with Arylacetylenes: VII. Regiochemistry of Reaction 2,2,2-Tribromo-5-halobenzo[d]-[1,3,2λ5]dioxaphospholes with Arylacetylenes

et al. 2005

Self Cite

View full text Add to dashboard Cite

It was for the first time shown that 2,2,2-tribromo-and 2,2-dibromo-2-fluoro-5-halobenzo[d]- [1,3,2l 5 ]dioxaphospholes react with arylacetylenes with preferential formation of heterocycles monohalogenated in the benzo fragment, viz. 4-aryl-2-bromo(fluoro)-7-halobenzo[e][1,2]oxaphosphinines. Their structure was established by NMR spectroscopy. By varying in such a way the nature of the halogen at the phosphorus atom one can obtain 6-or 7-halo-substituted regioisomers of benzo[e][1,2]oxaphosphinines.We recently showed that the reactions of a readily available P(V) halide, 2,2,2-trichlorobenzo[d][1,3,2l 5 ]-dioxaphosphole (I), with arylacetylenes or propargyl chloride give benzo[e][1,2]oxaphosphinines II and III. The reactions occur in mild conditions and involve formation of a phosphorus3carbon bond and phosphoryl group, as well as ipso-substitution of oxygen by carbon in the benzene ring. Depending on the nature of the alkyne, chlorine is regioselectively introduced para (with phenylacetylene) or ortho (with propargyl chloride) to the oxygen atom of the phosphinine ring [2, 3]. G g jCl 6 Ph O P d r O Cl 58 G g CH 2 Cl O P d r O Cl g Cl 8 II III Unlike compound I, 2,2,2-tribromobenzo[d]-[1,3,2l 5 ]dioxaphosphole (IV) reacts with arylacetylenes to form benzophosphinines V and VI, the latter having no bromine in the benzene ring [1]. 58 G g j Br 6 Ar O P d r O Br 58 G g Ar O P d r O Br V V I ÄÄÄÄÄÄÄÄÄÄÄÄ 1 For communication VI, see [1]. If starting trichlorobenzophosphole VII contains a 5-Br substituent, chlorine is introduced in the preferentially formed benzophosphinine occurs so that both halogens are ortho to each other and para to the fused phosphinine ring [4]. 5 j Br 5 K O O PCl 3 7776 PhC=CH [3HCl] 58 G g O P d r O Cl d j Br Cl 7 6 Ph VII VIIIIn the present work we for the first time studied reactions of P,P,P-tribromobenzophospholes halosubstituted in the phenylene fragment (compounds Xa and Xb) with arylacetylenes. Unlike what is observed with their chlorine analogs, the bromine atom in such tribromophosphoranes is not so favorably disposed toward migration into the phenylene fragment of the benzophosphinine formed, which might allow preparation of regioisomers (with respect to the position of the halogen atom) of compounds II and V.Phosphorane Xa (d P 3188.5 ppm, CH 2 Cl 2 ) containing chlorine in the benzene ring and obtained from derivative IXa reacts with phenylacetylene to form preferentially (more than 65%) a single benzophosphinine. In the 31 P NMR spectrum, the product gives a signal at d P 5.8 ppm ( 2 J PCH 27.0 Hz) and in the 1 H NMR spectrum (250 MHz, CDCl 3 ), a downfield doublet (d 6.20 ppm) with the same 2 J PCH constant. The 13 C NMR spectrum of the reaction mixture freed of volatile products in a vacuum, like the spectrum of

show abstract

Section: äääääääääääämentioning

confidence: 99%

Section: äääääääääääämentioning

confidence: 99%

Section: G Gmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Reaction of Trihalo(phenylenedioxy)phosphoranes with Arylacetylenes: VII. Regiochemistry of Reaction 2,2,2-Tribromo-5-halobenzo[d]-[1,3,2λ5]dioxaphospholes with Arylacetylenes

et al. 2005

Self Cite

View full text Add to dashboard Cite

show abstract

“…Hydrolysis of the latter leads to opening of the oxaphosphinine ring with formation of (E)-2-(4-chloro-2-fluoro-6-hydroxyphenyl)-2-phenylethenylphosphonic acid.* For communication VI, see [1]. …”

mentioning

confidence: 99%