Conformations of six-membered ring phosphorus heterocycles. Preferred axial orientation of methyl on phosphorus in a six-membered ring tert-butyl-substituted methylphosphonite

1971 ◽  
Vol 93 (3) ◽  
pp. 797-798 ◽  
Author(s):  
Wesley G. Bentrude ◽  
Kwok Chun Yee ◽  
Richard D. Bertrand ◽  
David M. Grant
Keyword(s):  
Membered Ring ◽  
Axial Orientation ◽  
Tert Butyl ◽  
Phosphorus Heterocycles

Cyclisierung von Di(tert-butyl-methyl)ketazin zu 1,2-Diaza-3-bora- und 1,2-Diaza-3-sila-cyclopent-5-enen / Cyclization of Di(tert-butyl-methyl)ketazine to 1,2-Diaza-3-bora- and 1,2-Diaza-3-sila-cyclopent-5-enes

2006 ◽  
Vol 61 (10) ◽  
pp. 1261-1274 ◽  
Author(s):  
Florian Armbruster ◽  
Nina Armbruster ◽  
Uwe Klingebiel ◽  
Mathias Noltemeyer ◽  
Stefan Schmatz
Keyword(s):  
Crystal Structures ◽  
Quantum Chemical Calculations ◽  
Chlorine Atom ◽  
Quantum Chemical ◽  
Membered Ring ◽  
Substitution Product ◽  
Tert Butyl ◽  
Isomeric Structures

The results of quantum chemical calculations on lithium ketazides suggest mainly four isomeric structures with different modes of lithium coordination (A-D). A monolithium ketazide thf-adduct (1) was isolated supporting the results of the quantum chemical calculations. In reactions of the lithiated di(tert-butyl-methyl)ketazine with BCl3 and Cl2BPh, 1,2-aza-azonia-3-borata-cyclopent-5-enes (2, 3) were isolated. Substitution of a chlorine atom of 2 and 3 with t-BuLi leads to the formation of derivatives 4 and 5. HCl elimination from 2 with Et3N gives - via a diazaboracyclopentene (6) - a bicyclus 7. In the reaction of the dilithiated ketazine with F2BN(SiMe3)2, the diaza-boracyclopentene 8 is obtained while with Cl4Si, F3SiN(SiMe3)2, and Cl2SiMe2 the diazasilacyclopentenes 9 - 11 are generated. SiF4 reacts with the dilithium ketazide to give a spirocyclus (12). The monolithium ketazide and Cl2SiMe2 react at 30 °C to give a four-membered ring isomer of the substitution product which is formed via a 1,3-chlorine shift from silicon to carbon (13). A tetrameric silanolate was isolated as a by-product in this reaction. It gives evidence for the structure of lithium ketazide A. Crystal structures of 5, 7, 10, and 14 are reported.

ChemInform Abstract: Conformations of Saturated Six-Membered Ring Phosphorus Heterocycles. 2-Aryl-1,3,2λ5-oxazaphosphorinanes.

ChemInform ◽  
1989 ◽  
Vol 20 (4) ◽  
Author(s):  
W. G. BENTRUDE ◽  
W. N. SETZER ◽  
A. E. SOPCHIK ◽  
S. CHANDRASEKARAN ◽  
M. T. ASHBY
Keyword(s):  
Membered Ring ◽  
Phosphorus Heterocycles

scholarly journals New Spiro-Tin Compounds: Reaction of N,N′-Dialkyl Sulfur Diimides with Cyclic Bis(amino)stannylenes - Unexpected Formation of a N-N Bond

1995 ◽  
Vol 50 (12) ◽  
pp. 1811-1817 ◽  
Author(s):  
Max Herberhold ◽  
Christian Köhler ◽  
Wolfgang Milius ◽  
Bernd Wrackmeyer
Keyword(s):  
Molecular Structure ◽  
Magnetic Resonance ◽  
Single Crystal ◽  
Structure Analysis ◽  
Membered Ring ◽  
Monoclinic Space Group ◽  
Unexpected Formation ◽  
Tin Compounds ◽  
X Ray ◽  
Tert Butyl

N,N′-Dialkyl sulfur diimides (1), R(NSN)R [R = Me (a), Et (b), nPr (c), nBu (d)] react with cyclic bis(amino)stannylenes such as 1,3-di-tert-butyl-4,4-dimethyl-1,3,4,2λ2-diazasilastannetedine (2) or 1,3-di-tert-butyl-4,4,5,5-tetramethyl-1,3,4,5,2λ2-diazadisilastannolidine (3) in a 2:1 ratio to give the new spiro-tin(IV) compounds 5a-d, 6b and 6c, built from the respective cyclic bis(amino)stannylene and a seven-membered ring in which the two sulfur diimide groups are coupled via a N-N bond and across the tin atom. A 1:1 adduct 4 is proposed as an intermediate which is the final product 4e in the case of R = tBu (1e). The products were characterized by multinuclear magnetic resonance (1H, 13C, 15N, 29Si, 119Sn NMR), and in the case of 5c the molecular structure was determined by single crystal X-ray structure analysis [monoclinic, space group C2/c ; a = 1504.1(3), b = 1393.3(3), c = 1688.6(3) pm; β = 115.71(3)°].

scholarly journals Crystal structure of tetraethyl 27,30-dioxo-7,12,20,25-tetra-tert-butyl-3,16-dioxa-9,22,28,31-tetrathiaheptacyclo[21.3.1.11,5.14,8.110,14.114,18.117,21]dotriaconta-4,6,8(29),10,12,17,19,21(32),23,25-decaene-2,2,15,15-tetracarboxylate

2015 ◽  
Vol 71 (10) ◽  
pp. o778-o779
Author(s):  
Mehmet Akkurt ◽  
Jerry P. Jasinski ◽  
Shaaban K. Mohamed ◽  
Omran A. Omran ◽  
Mustafa R. Albayati
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Membered Ring ◽  
Asymmetric Unit ◽  
Axis Direction ◽  
Tert Butyl ◽  
Envelope Conformation ◽  
Compound C ◽  
A Chain

The asymmetric unit of the title compound, C54H64O12S4, consists of one half of the molecule, which is located on an inversion centre. The heterocyclic six-membered ring adopts a distorted envelope conformation with the spiro C atom as the flap. In the crystal, molecules are linked by weak C—H...O hydrogen bonds with anR22(14) motif, forming a chain along theb-axis direction.

tert-Butyl 3-endo-3-hydroxy-8-azabicyclo[3.2.1]octane-8-carboxylate

2006 ◽  
Vol 62 (4) ◽  
pp. o1233-o1234
Author(s):  
Shuang-Wei Chen ◽  
Cai-Hong Xu ◽  
Guo-Rong Zheng ◽  
Xu-Hu Jin
Keyword(s):  
Dopamine Transporter ◽  
Title Compound ◽  
Chair Conformation ◽  
Membered Ring ◽  
Hydroxyl Group ◽  
Tert Butyl ◽  
Envelope Conformation ◽  
Compound C ◽  
Important Intermediate

The title compound, C12H21NO3, is an important intermediate for new dopamine transporter inhibitors. The six-membered ring of the azabicyclo[3.2.1]octane system adopts a chair conformation with the hydroxyl group axial. The fused five-membered ring is in an envelope conformation.

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