942
Organometallics, Vol. 2, No. 7, 1983
of Carbanions”, M. T. Reetz discusses a relatively new area of organometallic reagent chemistry, the applications of u-bonded organotitanium species, principally those of types RTiY3 and R2TiY2(Y = halide, alkoxy, dialkylamino) in organic synthesis. The reactions discussed involve in the main Grignard-type C = O additions, aldol condensations, Michael additions, and substitution reactions of alkyl halides, i.e., “classical” organometallic chemistry of the type known for many years already for organozinc, -magnesium, and -lithium reagents. In some cases the use of titanium reagents leads to an increase in chemo-, regio-, diastereo-, or enantioselectivity. In these days when almost every metal in the periodic table is being touted by someone or another the answer to the synthetic chemist‘s prayer, it seems that titanium indeed is one of the metals which actually will find some useful applications in organic synthesis. Two research groups appear to have started research independently in this area, more or less a t the same time, and the author seems concerned about questions of priority. Also, probably in part for this reason, the reader is treated to accounts of a good deal of unpublished work from the author’s laboratories. Reetz’s review is well organized and well written in good English. Some tables (Nos. 3 , 5 , 9 ) will cause the reader some exasperation because compound numbers are used for the reagent entry rather than the formulas. The other organometallic review is by H. Siegel, and it deals with ”Lithium Halocarbenoids and -carbanions of High Synthetic Versatility”. The scope is restricted to organic synthetic versatility, so this overview of this reagent class is by no means a complete one. Within this limitation this is a good review, bringing, as it does, the research results of those who have followed the earlier pioneers of this field. This short, 24-page review would have been more valuable to the interested reader if more examples of the various types of reactions had been provided by means of tables. The other two reviews are organic: ‘Pyridinophanes, Pyridinocrowns, and Pyridinocryptands”, by V. K. Majestic and G. R. Newkome, and “New Perspectives in Polymer-Supported Peptide Synthesis”, by V. N. R. Pillai and M. Mutter. There is one very ojectionable feature to this volume, one found in all four of the reviews: the liberal use of “et al.” in the collected references at the end of the reviews. Presumably, all of the people listed as authors of a paper have contributed to the work reported, 50 why should all but the first author be condemned to anonymity? Are authors getting lazy or is this an unfortunate editorial policy? Finally, there is the problem of price. At 226 a page, this book will be an expensive pleasure indeed for its purchasers! Dietmar Seyferth, Massachusetts Institute of Technology
Gmelin Handbook of Inorganic Chemistry. 8th Edition. Sb. Organoantimony Compounds. Part 2. Compounds of Trivalent Antimony with Two or One Sb-C Bonds. Stibabenzene. Stibacarboranes. M. Wieber, volume author. 1981. iii + 182 pages. DM 512, $232.70. Organoantimony Compounds. Part 3. Compounds of Pentavalent Antimony with Six, Five and Four Sb-C Bonds. M. Wieber, volume author. 1982. iii + 204 pages. DM 624, $260.20. Gmelin Institut fur Anorganische Chemie der Max-Planck-Gesellschaft zur Forderung der Wissenschaften and Springer-Verlag, Berlin/Heidelberg/New York. The first Gmelin organoantimony volume covered trivalent
Book Reviews compounds with three Sb-C bonds. Part 2 deals with all types of organoantimony compounds which contain one or two organic, carbon-bonded substituents per antimony atom. Included are organoantimony hydrides, halides, hydroxides, alkoxides, carboxylates, amides, and mercaptides of type RzSbY and RSbY,, as well as compounds with Sb-Si, Sb-P, Sb-MI, Sb-Ge, Sb-Sn, Sb-Pb, and Sb-transition-metal bonds. Also represented are dinuclear and polynuclear antimony compounds of diverse types, R2Sb-SbR2 and (RSb),, as well as those in which the antimony atoms are separated by organic or inorganic bridging groups. The reader is warned right at the beginning that many organoantimony compounds are very toxic and that the alkyl derivatives are air-sensitive and often prone to autoignition. Some are lightsensitive; some are vesiccants: a thoroughly unpleasant lot. Furthermore, they seem to have very few useful applications. Nonetheless, quite a few have been prepared over the years and all that is known about them (usually the bare minimum) is recorded here: preparation, physical properties, spectroscopic properties, and reactions, together with appropriate references. A compound of greater current interest is Ashe’s stibabenzene, which, although very labile and prone to polymerization, has been the subject of detailed spectroscopic studies (‘H and 13C NMR, UV, photoelectron, microwave) because the compound is of theoretical interest. Part 3 brings all that is known about compounds with six, five and four Sb-C bonds. Those with six Sb-C bonds have as sole representatives the interesting Li[SbPh6] and Li[SbPh5(C6H4CH3-p)].The most interesting property of the former, that, as Wittig reported, it can serve as a useful slow-release source of phenyllithium is not mentioned. Pentaorganoantimony compounds are dealt with next. Of these, the pentamethyl and the pentaphenyl derivatives have received the most attention, and 7 pages are required to bring all the known information concerning the latter as detailed in 53 references. The chemistry of the R5Sb compounds is quite varied and interesting and all sorts of mixed compounds, R,SbR’&,, may be prepared. A really good look at their reactivity with their utilization in organic and organometallic synthesis in mind might be a nice research project. The R,SbX-type derivatives may be ionic, [R,Sb]+X-, or covalent, R4Sb-x, depending on the substituent x. Many are known and, in fact, 134 of the 171 pages of text in Volume 3 are devoted to this class of compounds. With Part 3, the coverage of organoantimony compounds appears to be complete. In both books the literature cutoff date is 1978, but it is stated that “in some cases more recent data have been considered”. In the past, the Gmelin volumes usually have appeared more promptly, but now that they all are published in English rather than in German, a delay of the manuscripts of German authors is inevitable. The literature coverage is well-nigh exhaustive, being keyed to what “Chemical Abstracts” reports. The English is adequate, but it is obvious that the translator did not worry too much about niceties of usage and style. The main thing, of course, is that the science is comprehensible. As is true for all Gmelin volumes, these books are well produced with many tables and formulas. Each has its own formula index. These three volumes by Dr. Wieber may be recommended as excellent starting point for anyone who wants to know anything about organoantimony chemistry. Dietmar Seyferth, Massachusetts Institute of Technology
