New Aspects in Phosphorus Chemistry II

Buch | Softcover

X, 263 Seiten

2010 | 1. Softcover reprint of hardcover 1st ed. 2003
Springer Berlin (Verlag)
978-3-642-07900-9 (ISBN)

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Strong non-ionic bases are highly advantageous as stoichiometric reagents and as catalysts in synthetic organic chemistry owing to side reactions that f- quently occur when ionic bases such as LDA or alkali metal alkoxides are employed. A second reason that non-ionic bases are frequently more useful in these applications is that such bases are often more soluble in less polar organic solvents,particularly at low temperatures. Thirdly,non-ionic bases can provide reactive naked or tightly associated deprotonated substrate anions that are s- bilized by the relatively large,poorly solvated cations formed by the protonated base. In such cations,extensive positive charge delocalization can occur. Prior to our work on pro-azaphosphatranes of type 1 (Scheme 1),the very strong n- ionic bases utilized for organic transformations were largely confined to the nitrogenous bases shown below (Scheme 2). Scheme 1 Scheme 2 4 J. G. Verkade 2 Uses of Strong Nonionic Nitrogen Bases 2. 1 Amines One of the earliest strong non-ionic bases to make its appearance was Proton Sponge and its derivatives [1] and these systems have been reviewed [2]. More recently Proton Sponge has been used in the palladium-catalyzed arylation of 2,3-dihydrofuran [3], and it also catalyzes Knoevenagel condensations of s- strates possessing activated methylene groups [4]. Recently the synthesis of the macrocyclic tetramine below (Scheme 3) was reported [5]. The encrypted nitrogens are very basic (pK ,24.

P(RNCH2CH2)3N: Very Strong Non-Ionic Bases Useful in Organic Synthesis.- The Asymmetric Phospho-Aldol Reaction. Past, Present and Future.- Chemistry of Phosphanylidene Carbenoids.- Transient Nitrilium Phosphanylid Complexes - New Versatile Building Blocks in Phosphorus Chemistry.- What to do with Phosphorus in Dendrimer Chemistry.- Phosphonate Chemistry and Reagents in the Synthesis of Biologically Active and Natural Products.- The Fascinating Chemistry of 1,3,5-Triphosphinines and Valence Isomers [1].

Erscheint lt. Verlag	19.10.2010
Reihe/Serie	Topics in Current Chemistry
Co-Autor	P. Balczewski, A.-M. Caminade, H. Heydt, S. Ito, T.P. Kee, J.-P. Majoral, M. Mikolajczyk, T.D. Nixon, R. Streubel, J.G. Verkade, M. Yoshifuji
Zusatzinfo	X, 263 p.
Verlagsort	Berlin
Sprache	englisch
Maße	155 x 235 mm
Gewicht	416 g
Themenwelt	Naturwissenschaften ► Biologie ► Biochemie
	Naturwissenschaften ► Chemie ► Anorganische Chemie
	Naturwissenschaften ► Chemie ► Organische Chemie
Schlagworte	Anorganische Chemie • Biochemie • biochemistry • Inorganic Chemistry • natural product • Organic Chemistry • Organische Chemie
ISBN-10	3-642-07900-8 / 3642079008
ISBN-13	978-3-642-07900-9 / 9783642079009
Zustand	Neuware