Lithium, organic derivatives

TV-aluminum imines are another example of masked inline derivatives of ammonia. They are easily synthesized by partial reduction of nitriles with diisobutylaluminum hydride (D1BAL-H)6. Addition of lithium organic reagents to /V-aluminum iniines 7 derived from O-protected cyanohydrins 6 provides a-amino alcohols 8a and 8b in moderate yields and low to good diastereo-selectivities n 12. 

Lithium salts of resonance-stabilized organic anions have also found a role in carbon-phosphorus bond formation by displacement at phosphorus. The generation of the lithium salt derived from acetonitrile (or other aliphatic nitriles by reaction with butyl lithium or lithium diisopropylamide) provides for carbon-phosphorus bond formation by displacement of halide from phosphorus (Equation 4.24).68... 

Of course, it is not without precedence as there are already various reviews and textbooks in the area. Most closely related to this work are the reviews by Setzer and Schleyer and by Weiss °. A textbook edited by Sapse and Schleyer contains chapters on various topics of lithium chemistry. Three reviews by StaUce, Harder and by Jutzi and Burford concentrate on cyclopentadienyl organometallic derivatives, containing also the s-block derivatives. Two reviews deal with the heavier alkali metal organics, the first written by Schade and Schleyer , the second by Smith . There are several chapters on lithium organics within more general metal organic publications ... 

Electrophilic and nucleophilic reactions of 2-(2-thienyl)thieno[2,3-cf pyrimidine (346), prepared as shown in Scheme 99, permits a conclusion concerning the reactivity compared with that of thiophene bearing an electron deficient substituent in position 2. Both nitration and bromination primarily occur in the thiophene moiety whereas lithium organic reagents (methyllithium, butyllithium) add at carbon atom 4 (77BSF676). Bromination of (324) yields the 5- (or 6-) bromo derivative (68CR(C)(267)697). 

The structures of the organic derivatives of the Group IA and IIA metals are not simple because many of them involve molecular association. For example, the lithium alkyls are tetramers in which the lithium atoms reside at the corners of a tetrahedron and the carbon atoms bonded to them are located above the triangular faces of the tetrahedron as shown in Figure 7.2. 

Reactions of tin(IV) halides or organotin halides with organic derivatives of more electropositive metals provide the most important general synthetic routes to carbon-tin bonds (equation 6). The most frequently used R -M compounds are those of magnesium and lithium, with sodium, zinc, and aluminum having a more limited use. Some examples of these reactions are given in equations (7-9). 

Apart from organic derivatives of pentazene, N5H5, the cyclic compound 78 is, so far, the only other Group IV derivative of this hydride (35). It is formed by the action of ethyl nitrite on the silylated lithium hydrazide 77 in diethyl ether at -78 C [Eq. (99)]. It is a colorless crystalline... 

Addition of lithium enolates derived from esters and ketones to epoxides has been the object of some consideration, because it offers a direct route for the synthesis of y -hydroxy esters and y-hydroxy ketones, very useful for difunctionahzed organic compounds" . In fact, more complex molecules can be synthesized by using these compounds as synthons... 

The polymerization of propiolactoue by organic derivatives of zme, c cadmium or aluminum requires the presence of a ou-catalyst, water or oxygen this is not so with organio derivatives ot lithium, sodium, potassium or magnesimn,... 

Metathesis reactions are common in the preparation of organic derivatives of elements, using organo-lithium or -magnesium (Grignard) reagents produced by direct synthesis ... 

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