The present volume is a continuation of Series B on the mononuclear organoiron compounds. It covers the literature completely to the end of 1979 and includes occa- sional references to the literature up to 1982. This volume begins the description of compounds with 5L ligands, i.e., ligands bonded to the iron atom by five carbon atoms. 5LFe compounds are numerous, particu- larly those where 5L is cyclopentadienyl. The stability of a 5LFe unit permits many different ligands at the other three coordination sites of the iron atom. Thus the present volume can only cover apart of the 5L compounds. Main sections of the volume deal with 5LFe compounds containing other ligands of the D and X type and 5LFe compounds with an additional' L ligand, which include compounds with 5LFe(CO) units (complete in this volume) and 5LFe(CO)2 units (to be continued in B 12). Series B so far comprises volumes B 1 to B 7, and a survey of this series has been given in the preface to B 7 (1981). The missing parts, B 8 to B 1 0, describe the remain- ing 4LFe compounds and will appear in the near future.

This fifth volume on organoantimony compounds continues the description of pentavalent antimony compounds and concludes the entire series. The treatment of pentavalent compounds with three Sb-C bonds began in Part 4 with the RSbX type and is now completed with types RSb(X)Y, RR'SbX , RR'Sb(X)Y, 3 2 3 2 2 2 RR'R"SbX (Section 2.5.1) and the corresponding bi- and trinuclear compounds (Sec- 2 tions 2.5.2, p.87, and 2.5.3, p. 132). R, R', and R" denote different organic groups bonded through carbon to the antimony atom. X and Y represent inorganic or organic groups that are bonded to antimony by an atom other than carbon. R, X, and/or Y can also be chelating ligands. The remaining part of the volume completeLy covers all pentavalent antimony compounds containing two Sb-C bonds (RSbX , RSb(X )Y, RR'SbX , RR'Sb(X )Y, bi- and tetranucLear 2 3 2 2 3 2 compounds, Chapter 2.6, p. 134) and those containing one Sb-C bond (RSbX , RSb(X )Y, 4 3 RSb(X)Y , bi- and trinucLear compounds, Chapter 2.7, p. 237). These compounds form ad- 2 2 ducts with Lewis bases (symbol D) and form many ionic compLexes by the addition of saLts such as amine hydrochLorides (symbol MZ). The adducts and ionic compLexes are described immediately after the parent substances. The volume concludes with an Empirical Formula Index (p. 318) and a Ligand Formula Index (p. 357).

This fourth volume on organoantimony compounds describes pentavalent antimony com- pounds of the type R and R . The R denotes an organic group bonded by carbon 3SbX2 3Sb=X to the antimony atom. X represents a group, inorganic or organic, which is bonded to the antimony by an atom other than carbon. The X atoms in R may be part of a 3SbX2 ring system. In the case of bidentate X ligands like 02- , S2-, SO~-, CO~-, and others, the compounds are placed with the mononuclear RssbX compounds. 2 I once again thank Dr. Margot Becke and Dr. Ekkehard Fluck for the stimulus that led to this book. To the editor of the former volumes, Dr. Hubert Bitterert gratitude and memory are due. I especially thank Drs. Ulrich Kruerke and Marlies Mirbach for editing this volume, Mrs. Ursula Hettwer for systematically arranging the compounds, and Mr. Edgar Rudolph for preparing the index. Last but not least I thank my wife Sigrid for putting my handwritten manuscript into legible form. Gramschatz, Altes Forsthaus, June 1986 Markus Wieber x Explanations, Abbreviations, and Units Many eompounds in this voLume are presented in tabLes in whieh abbreviations are used and the units are omitted for the sake of eoneiseness. This neeessitates the foLLowing ctarifieation.

The present volume describes organoberyllium compounds containing at least one berylli um-carbon bond, except the beryllium carbides and cyanides. It covers the literature com pletely to the end of 1986 and includes most of the references up to mid-1987. This Gmelin volume is different from all other volumes of the series on organometallic compounds in that it is dedicated to an area of research which has virtually come to a complete standstill. Organoberyllium chemistry has never been a very popular field, and only few workers have contributed to its slow growth, as is seen by the relatively small number of publications in the field. This very modest development became stagnant in the early 1970's and was followed by a rapid decline. This exceptional fate of a branch of organometallic chemistry is only partly due to the very limited number of potential application~ of beryllium and its compounds. The compounds of this element are, in principle, at least as interesting and intriguing to scientists as those of other metals in the Periodic Table. No doubt the main reason for the apparent ban of all experimental organoberyllium chemistry is to be found in the established, and alleged, hazardous properties of beryllium compounds. Although similar hazards have been established for other organometallics where active research is still in process, e. g. , mercury and lead, these observations were absolutely lethaI for organoberyllium research.

The present voLume continues the series on "Organotin Compounds" which first appeared in 1975 and now comprises a coLLection of fourteen voLumes. The overaLL pLan of the series has been given in the preface of VoLume 1. The present VoLume 14 continues the description of the mononucLear organotin compounds with tin-oxygen bonds (Chapter 1.4.1). Treatment of organotin compounds with tin-sulfur, -selenium, and -teLLurium bonds appeared earLier in Chapters 1.4.2 to 1.4.4 of VoLumes 9, 1982, and 10, 1983. VoLume 14 contains RSn-oxygen compounds with R = methyL, ethyL, and prapyL, covering 2 the Literature compLeteLy to the end of 1985. AdditionaL voLumes describing tin-oxygen compounds with other RSn and RSn groups with foLLow in the near future. 2 Abbreviations and symboLs are expLained on pp. X/XI aLong with other remarks. We thank Prof. Dr. Dr. h. c. Ekkehard FLuck and his coworkers at the GmeLin Institute for their exceLLent cooperation. In particuLar, we thank Dr. ULrich Kruerke for his accurate and sympathetic editing, Mr. Edgar RudoLph for preparing the index, Dr. Grant for reading the EngLish text, and Mr. Hans-Georg Karrenberg for drawing the numerous formuLas and moLec uLar structures. We thank Mrs. ELLen Redlinger, Miss Susanne Schumann, and Miss Stefanie Schumann for their meticuLous handling of the Literature index and the members of the chemicaL department of the Library at the Technische Universitat Berlin for their assistance in searching and acquiring the references fram the Literature."

The present volume continues the series on "Organotin Compounds" which first appeared in 1975 and now comprises a collection of fifteen volumes. The overallplan of the series has been given in the preface of Volume 1. The present Volume 15 continues the description of the mononuclear organotin compounds with tin-oxygen bonds (Chapter 1.4.1 ). Treatment of organotin compounds with tin-sulfur, -selenium, and -tellurium bonds appeared earlier in 9, 1982, and 10, 1983. Chapters 1.4.2 to 1.4.4 of Volumes Volume 15 contains RSn-oxygen compounds with R = butyl, iso-butyl, sec-butyl, and 2 tert-butyl, covering the Literature completely to the end of 1985. Additional volumes describing tin-oxygen compounds with other RSn and RSn groups will follow in the near future. 2 Abbreviations and symbols are explained on pp. X/XI along with other remarks. We thank Prof. Dr. Dr. h. c. Ekkehard Fluck and his coworkers at the Gmelin Institute for their excellent cooperation. ln particular, we thank Dr. Ulrich Kruerke for his accurate and sympathetic editing, Mr. Edgar Rudolph for preparing the index, Dr. Grant for reading the drawing the numerous formulas and molec English text, and Mr. Hans-Georg Karrenberg for ular structures. We thank Mrs. Ellen Redlinger, Miss Susanne Schumann, and Miss Stefanie Schumann for their meticulous handling of the Literature index and the members of the chemical department of the Library at the Technische Universitat Berlin for their assistance in searching and acquiring the references from the Literature."

The present volume in the organogermanium series describes mononuclear compounds containing only germanium-carbon and germanium-hydrogen bonds (Chapter 1.3). Germanium hydrides with other additional non-carbon ligands, such as halogen or oxygen bonded groups, appear in later chapters according to the Gmelin principle of the last posi tion. Compounds with Ge-H and Ge-O bonds have already been described in Volume 5, Section 1.5.1.4, pp. 50/62. The present volume covers the literature to the end of 1992 and includes many references up to 1994. The nomenclature recommended by IUPAC has been generally adhered to. However, compound names were largely avoided, as most of the compounds are presented in tables and are only identified by their formulas. Many of the data in the tables appear in abbreviated form without units; general explanations are given on pp. X/XI. The volume contains an empirical formula index (p. 327) and a ligand formula index (p.341). The editor wishes to express his gratitude to the former author, Professor J. E. Drake, and to Professor J. Satge for his kind advice and fruitful collaboration. Thanks are due also to Dr. A. R. Pebler for editing the English text and to Mr. H.-G. Karrenberg for drawing the numerous formulas and molecular structures.