Synthetic Principle Research Articles

Umpolung of o-phenylenediamines by conversion into isobenzimidazole. An expedient approach to heterocycles with nucleophilic substituents

Isobenzimidazole-2-spirocyclohexane(1)can be made to react with nitrogen, oxygen, sulphur, and carbon nucleophiles to give mono-and di-substitied derivatives. On reductive ring-opening the correspondingly substituted o-phenylenediamine is obtained. The scope of this synthetic principle has been studied and the reaction used to prepare various heterocycles with substituents that are difficult to introduce by conventional methods. Selenadiazole or its 4-chloro and 4,5-dichloro derivatives were found to be unsuitable alternatives to (1).

Application de la réaction de métathèse à la synthèse de prépolymères α,ω‐bifonctionnels, 2. Etude de possibilitiés d'application à la synthèse de prépolymères α,ω‐dichlorés

AbstractThe capability of chloroalkenes to undergo cometathesis with alkenes was investigated with the intention to check the possibility of applying the principle of the synthesis of α,omega;‐difunctional polybutadienes to α,omega;‐dichloropolybutadienes. The results obtained from the analysis of the reaction products resulting from 1,6‐dichloro‐3‐hexene (1)/4‐octene (2) systems and WCl6/EtAlCl2 were compared with those obtained from 1‐chloro‐3‐hexene (8) alone, 1/1,5‐cyclooctadiène (13), 5‐chloro‐1‐pentene (6)/2, and 1,4‐dichloro‐2‐butene (10)/2 systems in the presence of WCl6/EtAlCl2. It was found that it is possible to apply the synthetic principle to α,omega;‐bis‐(δ‐chloroalkenyl)polybutadienes.

Dimerization and oligomerization by dehydrogenation as a general synthetic principle (1) part III

Dimerization and oligomerization by dehydrogenation as a general synthetic principle (1) part III

Dimerisation and oligomerisation by dehydrogenation as a general synthetic principle (1) part I

Dimerisation and oligomerisation by dehydrogenation as a general synthetic principle (1) part I

Dimerisation and oligomerisation by dehydrogenation as a general synthetic principle (1a) part II

Capto-dative substituants determine the ease of selective hydrogen abstraction, but steric factors and the nature of the dehydrogenating agent influence the relative “radical scale”. This study underlines the value of preparative work in dehydrodimerizations. The method also allows the preparation of oligomers and polymers.

An Effective Synthetic Principle for Amino Sugars of the Daunosamine Type

An Effective Synthetic Principle for Amino Sugars of the Daunosamine Type

Synthesis of Pyrrolo[3,4-c]pyrazole Derivatives by Intramolecular Cycloaddition of Nitrile Imines

Abstract We have recently shown that furo[3,4-c]pyrazole and furo[3,4-c]isoxazole derivatives are available through a reaction sequence including the intramolecular cycloaddition of properly functionalized 1,3-dipoles1. As a confirmation of the wide applicability of this synthetic principle, the preparation of pyrrolo[3,4-c]pyrazoles is here reported. Representatives of this ring system, often of interest in pharmacology, have been previously synthesized by the reaction of properly 4-substituted pyrroli din-3-ones with hydrazines2–7 or by the cycloaddition of diazocompounds to maleimides8–13.

Some Arguments Concerning the Principle of Sufficient Reason and Cosmological Proofs

SOME ARGUMENTS CONCERNING THE PRINCIPLE OF SUFFICIENT REASON AND COSMOLOGICAL PROOFS "Laws like the principle of sufficient reason . . . are about the net and not about what the net describes." (Ludwig Wittgenstein) "What a pity science cannot resolve to keep people under discipline and to keep itself in check!" (Kierkegaard 's Vigilius Haufniensis) RCENT literature concerning cosmological proofs for the existence of God has stressed their employment of the principle of sufficient reason (PSR). Though in the past many critics of theistic arguments have not only not recognized the operation of this principle but also have criticized theists for employing a version of the principle of causality explicitly rejected by many in the theistic tradition/ contemporary criticism has generally acknowledged the functioning of the PSR. This is not to .say, however, that the principle has not been found wanting. In fact, confining ourselves just to discussions of what we might call in a preliminary way its " truth," two types of criticism seem to have been advanced. The first type, developing a characterization used by James F. Ross, might be called "Humean" so as to stress its epistemological character as well as its similarity with standard empiricist procedures against the principleof causality. The other type, which might be called " theological," attempts to reveal the incompatibility of the PSR with the existence of 1 See W. Norris Clarke, S. J., "A Curious Blindspot in the Anglo-American Tradition of Anti-Theistic Argument," The Monist, 54 (1970), pp. 181-~00. ~58 SUFFICIENT REASON AND COSMOLOGICAL PROOFS fl59 a free creator God; the PSR must thus be repudiated by traditional theists themselves. Our first concern, in section I, will be a presentation of various " Humean" arguments as they have been developed by Professor Ross 2 and by Professor William L. Rowe.3 In section II we shall develop and discuss their criticisms of the PSR in an effort to come to a correct understanding of the meaning, status, and function of the principle. Our contention will be that both critics and defenders have not always been clear on these issues, especially on the difference between " Rationalist " and " Aristotelian " understandings of the PSR and cosmological argumentation. We shall argue that there are at least two ways the PSR oan be denied, that there is a different type of absurdity involved in each denial, and that the context and nature of the denials must be stressed by one who would successfully defend the principle. In view of the complex structure of the " theological " ·argumentation of both Ross and Rowe, and since much of what we would say in response would be a reiteration of what was developed earlier, we shall confine ourselves in section III to a presentation of what we consider the basic claims of this type of critique. Our analysis in section IV will stress the essential modesty of the " Aristotelian " PSR; instead of providing the basis for an overbearing rationalism, scientism, and determinism, this PSR seemingly functions to render philosophical theology a discipline which attains its goal in a simultaneous recognition of its essential incompleteness with regard to possible truths about the divine. 2 James F. Ross, Philosophical Theology (Indianapolis and New York: The BobbsMerrill Company, 1969). 3 In "The Cosmological Argument and the Principle of Sufficient Reason," Man and World, 1 (1968), pp. ~78-9~. In "The Cosmological Argument," No-Us, 5 (1971), pp. 49-61, Rowe presents a "theological" argument, but in the process clarifies his formulations of the PSR. (Our essay was written previously to the publication of Rowe's more detailed analyses in his The Cosmological Argument (Princeton: Princeton University Press, 1975)). 260 CHARLES J. KELLY I. The following four objections to the PSR havebeen advanced (the first two by James F. Ross, the third and fourth byWilliam L. Rowe): 1. Since the principle that everything has (must have) an explanation or sufficient reason is assumed without proof, how is it known to be true? Any attempt to establish it as true runs into the dilemma: a) If the PSR is known by induction its absolute universality cannot be established. It can only be a synthetic principle of doubtful truth, since a finite body of evidence is available which could...

On 'Unconventional' Sources Of Petroleum Hydrocarbons

Abstract As well as being recoverable from oil sands and oil shales, "petroleum hydrocarbon" (i.e. liquid fuels, industrial solvents, lubricating oils and greases, waxes, etc.) can be produced from a variety of other feedstocks. Examples are coal, coal tar, cellulosic wastes, carbon monoxide + hydrogen, and carbon monoxide + water. This paper outlines the methods by which liquid fuels can be made from non-petroleum hydrocarbon, and note that, in several instances, a fairly highly developed technology for such "fuel conversation" is already available. Introduction As THE MORE easily accessible indigenous oil reserves are depleted, and oil prices rise beyond a nominal $5–6 per barrel, the alternatives that offer themselves as replacements or supplementary sources of petroleum hydrocarbons include raw materials and processes which, although occasionally used in times of emergency, could so far otherwise not compete against conventional petroleum and petroleum refining. Having regard to the extent of projected North American oil demands, and to the enormous potentials represented by offshore and "frontier" oil accumulations, oil sands and oil shales, it can perhaps be taken for granted that future oil supplies will, for the most part, be drawn from these resources. This said however, it is also important to observe that fuel conversion technology and hydrocarbon synthesis have reached a stage of development where it becomes possible to all but disregard classical distinctions between solid, liquid and gaseous fuels, and to consider almost any form of carbon as a potential source of "petroleum hydrocarbons". In the decade ending with the second world war, Germany thus met the greatest part, and Britain some, of their respective needs of automotive and aviation fuels, industrial solvents and other petrochemicals by hydrogenation of coal and coal tars. South Africa is now covering 20–25 percent of her gasoline and petrochemical requirements by Fischer-Tropsch syntheses, using a coal-derived syngas as feedstock for this purpose. Several other countries, the U.S. among them, are now also manufacturing ammonia, methanol and certain plastics precursors by similar methods. This paper is therefore intended to summarize what has been and could, technically, now be done to exploit non-petroleum hydrocarbons as sources of liquid fuels. What makes this timely is the fact that several of the relevant technologies are now clearly moving into the realm of the economically feasible and emerging as vital components in the United States' drive toward energy self-sufficiency. There are indeed already some indications that updated conversion processes, partly being developed in the U.S. from earlier British and German techniques, may on occasion prove preferable to the recovery of conventional oil and gas from the geographically more remote reservoirs that would otherwise have to be brought into play*. The Principles of Synthetic Liquid Fuels Production In principle, the distinction between solid, liquid and gaseous fossil fuels lies ultimately in their hydrogen contents.

Synchronous Six‐Electron Cyclization of Hexatriene Systems as a New Synthetic Principle for Preparation of Aromatic and Heteroaromatic Compounds

Synchronous Six‐Electron Cyclization of Hexatriene Systems as a New Synthetic Principle for Preparation of Aromatic and Heteroaromatic Compounds

Structure and reactivity of polycyclic cross-conjugated π-electron systems

Abstract

1,2‐Dehydrobenzene

AbstractThe historical development of the methods to generate dehydrobenzene is outlined. Dehydrobenzene readily adds nucleophilic as well as electrophilic partners. Diels‐Alder addition to dienes is moreover a valuable synthetic principle. The intermediacy of dehydrobenzene has been proved for polar additions by labeling with 14C or with a substituent. The same conclusion has been reached in Diels‐Alder additions by competition experiments. The considerable selectivity displayed by dehydrobenzene in both types of reaction is not caused by solvation, since recently the existence of dehydrobenzene in the gas phase has been established, where it reacts similarly as in solution.

1,3‐Dipolar Cycloadditions. Past and Future

AbstractIn contrast to the very large number of special methods applicable to syntheses in the heterocyclic series, relatively few general methods are available. The 1,3‐dipolar addition offers a remarkably wide range of utility in the synthesis of five‐membered heterocycles. Here the “1,3‐dipole”, which can only be represented by zwitterionic octet resonance structures, combines in a cycloaddition with a multiple bond system – the “dipolarophile” – to form an uncharged five‐membered ring. Although numerous individual examples of this reaction were known, some even back in the nineteenth century, fruitful development of this synthetic principle has been achieved only in recent years.

Modern Theories of Development: an Introduction to Theoretical Biology

THIS important introduction to theoretical embryology is well-known to all those interested in the subject. The English translation and adaptation by Dr. Woodger will make it available to a wider circle of readers. The author proposes as a solution to the crisis of present-day biology, the constitution of a purified science which would relate and explain the accumulated facts pertaining to the study of living organisms. As a synthetic principle of this science, the author proposes an organismic theory which would aim at the establishment of the laws of biological systems based on experimental data and on the possible use of mathematical logic.

A Synthetic Principle in American Social History

A Synthetic Principle in American Social History

The Synthetic Principle in Butler's Ethics

Previous articleNext article FreeThe Synthetic Principle in Butler's EthicsH. G. TownsendH. G. Townsend Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 37, Number 1Oct., 1926 Article DOIhttps://doi.org/10.1086/intejethi.37.1.2378208 Views: 2Total views on this site Journal History This article was published in The International Journal of Ethics (1890-1938), which is continued by Ethics (1938-present). PDF download Crossref reports no articles citing this article.

The Synthetic Principle in Butler's Ethics

The Synthetic Principle in Butler's Ethics