International Union of Pure and Applied Chemistry
Organic Chemistry Division
Commission on Nomenclature of Organic Chemistry

TREATMENT OF VARIABLE VALENCE IN ORGANIC NOMENCLATURE (λ CONVENTION)

Recommendations 1983

Prepared for publication by W. H. Powell and published in Pure Appl. Chem., 1984, 56, 769-778.

https://iupac.qmul.ac.uk/hetero/Lm.html

World Wide Web version prepared by G. P. Moss

School of Physical and Chemical Sciences, Queen Mary University of London,
Mile End Road, London, E1 4NS, UK
g.p.moss@qmul.ac.uk

These Rules are as close as possible to the published version [see W. H. Powell Pure Appl. Chem., 1984, 56, 769-778. Copyright IUPAC; reproduced with the permission of IUPAC]. If you need to cite these rules please quote this reference as their source. A PDF of the printed version is available.

See also Chem. Listy, 1985, 79 1281-1286. (in Czech); F C Alderweireldt, H J T Bos, L Maat and D Tavernier, Regels voor de nomenclatuur van de organische chemie, sectie D, lambda-conventie, delta-conventie, Koninklijke Nederlandse Chemische Vereniging, Koninklijke Vlaamse Chemische Vereniging, 1990, ISBN 90-71446-04-2 (in Dutch) and Wiad. Chem., 1989, 43 93-102 (in Polish).

For problems in converting the text into a World Wide Web version see the IUPAC home page.

Any comments, corrections or suggestions for a future edition should be e-mailed to g.p.moss@qmul.ac.uk

Important Note: This version is formatted using the font symbol for Greek letters. If you cannot see a Delta (a triangle) in quotation marks next "Δ" click here for a version where Greek letters are created using graphic images.

CONTENTS

INTRODUCTION

Preamble
Introduction
Discussion
References for this section
RECOMMENDATIONS
Lm-1.0. Terminology
Lm-1.1. Bonding Number
Lm-1.2. Standard Bonding Number
Lm-2.0. Designation of Nonstandard Bonding Numbers
Lm-3.0. Indicated Hydrogen
Lm-3.1. Maximum Number of Noncumulative Double Bonds
Lm-3.2. Indicated Hydrogen Symbolism
Lm-4.0. Derivatives of Parent hydrides
Lm-4.1. Saturation of Double Bonds
Lm-4.2. Multiple Bonds with a Saturated Parent Hydride
Lm-4.3. Derivatives
Lm-4.4. Prefixes
REFERENCES

Continued with Lambda Convention Introduction

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