排序方式: 共有5条查询结果,搜索用时 15 毫秒
1
1.
K.C. Kumara Swamy G. Gangadhararao R. Rama Suresh N.N. Bhuvan Kumar Manab Chakravarty 《Journal of organometallic chemistry》2010,695(7):1042-382
Phosphine-activated reactions of alkynes/alkenes/allenes as well as the Mitsunobu reaction involve a rich phosphorus chemistry. With the aid of simple cyclodiphosphazanes, characterization of many compounds analogous to the proposed intermediates in such reactions has been accomplished. Use of a cyclodiphosphazane in Pd-catalyzed N-arylation reactions is highlighted. Results on molecular non-stoichiometry in phosphorus compounds and on the use of chiral phosphorus systems are discussed. Synthesis of allenylphosphoramides involving a cyclodiphosphazane is also described. X-ray structures of the new compounds [(t-BuNH)(PhCH2CH(CN)CH2-)P(μ-N-t-Bu)2P(NH-t-Bu)]+[HCO3]− (13), [(t-BuNH)P(μ-N-t-Bu)2P(N-t-Bu)-C(CH2)CH(C6H4-4-Me)-P(O)(OCH2CMe2CH2O)] (18), [(i-PrNH)P(μ-N-t-Bu)2P(N-i-Pr)-N(CO2-i-Pr)-NH(CO2-i-Pr)] (24), [(S)-(2-OH-1-C10H6-1′-C10H6-2′-O-P(O)(NH-t-Bu)2] (36) and [(t-BuNH)(O)P(μ-N-t-Bu)2P(O)(CHCCMe2)] (40) are also reported. 相似文献
2.
K. C. Kumara Swamy R. Rama Suresh G. Gangadhararao M. Anitha 《Phosphorus, sulfur, and silicon and the related elements》2016,191(11-12):1427-1432
ABSTRACTIn this article, we describe some of our results on the reactions of allenylphosphonates/allenyl phosphine oxides and allenyl diazaphosphole oxides, primarily cycloaddition and cyclization reactions. Depending on the substituents, both the α,β and β,γ -cycloaddition products have been observed. A novel cyclization reaction of a functionalized allenylphosphine oxide with diethylamine leading to 3-diethylamino-4-diphenylphosphinoyl-1-naphthol is reported. Representative compounds have been characterized by X-ray crystallography. 相似文献
3.
Deevi Basavaiah Gangadhararao Golime Shivalal Banoth Saidulu Todeti 《Chemical science》2022,13(27):8080
We have described the first example of an umpolung strategy for intermolecular [2 + 2 + 1] cycloaddition between two aryl aldehydes and a nitrile under the influence of TMSOTf that proceeds through the formation of N–C, O–C and C–C bonds providing a simple synthetic protocol for obtaining 2,4,5-trisubstituted oxazoles.An unprecedented intermolecular [2 + 2 + 1] cycloaddition strategy between two aryl aldehydes and a nitrile, wherein one of the aryl aldehydes serves as a carbanion (or equivalent) in the presence of TMSOTf for obtaining oxazole framework is presented. 相似文献
4.
K. C. Kumara Swamy M. Phani Pavan Mandala Anitha G. Gangadhararao 《Phosphorus, sulfur, and silicon and the related elements》2018,193(2):81-87
In this paper, we describe convenient methods for functionally active phenol addition reaction of allenylphosphonates/allenyl phosphine oxides. These reactions lead to either vinyl or allylphosphonates. In the reaction α-aryl allenylphosphonates with 2-iodophenol in the presence of Pd nanoparticles [Pd-PVP] isomeric vinylphosphonates are preferentially obtained. A novel cyclization reaction of 2-iodo-t-butylbenzaldimine with and allenylphosphine oxide that leads to an isoquinoline is also discovered; the product is characterized by single crystal X-ray structure determination. 相似文献
5.
The apparently simple reaction of the P(III) precursors [(RNH)P(μ-N-t-Bu)2PY] (Y=NH-t-Bu, Cl), (OCH2CMe2CH2O)PCl, and Ph2PCl with functionalized propargyl alcohols is examined. In most cases, the final products are not the expected allenes but several previously unpredicted structural motifs, such as substituted oxazabenzocycloheptenones, indolinones, and fused heterocycles as revealed by X-ray crystallography. Mechanistic aspects of these novel reactions, as well as possible utility and the structural chemistry of the products are also discussed. The P–C or P–N bond cleavage of many of these compounds led to phosphorus-free 2-substituted indoles, quinolinones, and tetrahydroacridine. 相似文献
1