Synthesis and unique reversible splitting of 14-membered cyclic aminomethylphosphines on to 7-membered heterocycles.
نویسندگان
چکیده
A novel type of 14-membered cyclic polyphosphine, namely 1,8-diaza-3,6,10,13-tetraphosphacyclotetradecanes 2a–4ahas been synthesized by the condensation of 1,2-bis(phenylphosphino)ethane, formaldehyde and alkylamines (isopropylamine, ethylamine and cyclohexylamine) as a RRRR/SSSS-stereoisomer. The structure of macrocycle 2a was investigated by NMR-spectroscopy and X-ray crystal structure analysis. The unique reversible processes of macrocycles 2a–4a splitting onto the corresponding rac- (2b–4b) and meso- (2c–4c) stereoisomers of 1-aza-3,6-diphosphacycloheptanes were discovered.
منابع مشابه
Ultrasonic-assisted Synthetic Improvement of Fluorinated Five- and Six-membered Triazolotriazine and Triazinophthalazine Heterocycles
In this investigation a simple synthetic method for the synthesis of trifluoromethyl-1H-benzo[e][1,2,4]triazolo[1,2-a][1,2,4]triazine-1,3(2H)-diones and (trifluoromethyl)benzo [5,6][1,2,4]triazino[1,2-b]phthalazine-8,13-diones has been developed using urazole or phthalazine and aceteimidoyl chloride derivatives at room temperature under ultrasound irradiations. In the comparison to the conventi...
متن کاملSinglet-Triplet Energy Splitting of Divalent Five-Membered Ring NI2C2H2C (M = N,P, As and Sb)
In recent work, thermal energy gaps. AE, it °PUPS gas, Ana; Gibbs free energy gaps, AG.,, between singlet(s) and triplet 0) states of 5.12C3H2C, I m (4 N. P. As and Sb) were calculated and compared with thoseanalogues. MC2113C, (M= CIL N. P. As and Sb) at B3LYIE6-311-NG" level of theory. Our itself showedthat Gibbs free energy gaps. AG, for l uu and 1 p are less than IS and I's, respectively. I...
متن کاملLow catalyst loadings in olefin metathesis: synthesis of nitrogen heterocycles by ring-closing metathesis.
A series of ruthenium catalysts have been screened under ring-closing metathesis (RCM) conditions to produce five-, six-, and seven-membered carbamate-protected cyclic amines. Many of these catalysts demonstrated excellent RCM activity and yields with as low as 500 ppm catalyst loadings. RCM of the five-membered carbamate series could be run neat, the six-membered carbamate series could be run ...
متن کاملTetrahedron Letters,Vol.23,No.9,pp 1003-1006,1982 0040-4039/82/091003-04$03.00/O PrInted In Great Brltaln 01982 Pergamon Press Ltd. OXIDATION OF N-HYDROXYAZETIDINES: A NOVEL SYNTHESIS OF N-ACETOXY 6-LACTAMS AND FOUR-MEMBERED CYCLIC NITRONES
The N-hydroxyazetzdznes 2 and 2 are prepared startzng from 2,3-dihydroazete I-oxzdes (la and lb) by reductzon wzth sodzum borohydrzde and by reactzon wzth a nucteophz~,resp~tzvely The N-hydroxyazetidznes 2 and 3 can be oxidzzed wzth mercuryfII)oxzde to the correspondzng nztrones 1, ox?datzon of the N-hydroxyazetzdzne 2a (unsubstztuted at C-41 wzth two equzvalents of Lead tetraacetate yzetds the...
متن کاملThe conversion of allenes to strained three-membered heterocycles.
This article reviews methods for converting allenes to strained, three-membered methylene heterocycles, and also covers the reactivity of these products. Specifically, the synthesis and reactivity of methylene aziridines, allene oxides/spirodiepoxides, methylene silacyclopropanes, methylene phosphiranes, and methylene thiiranes are described, including applications to the synthesis of complex m...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Dalton transactions
دوره 44 30 شماره
صفحات -
تاریخ انتشار 2015