methenen.

Brit.

/ˈmiːθiːn/,

/ˈmɛθiːn/, U.S.

/ˈmɛˌθin/

Origin: Formed within English, by compounding; modelled on a German lexical item. Etymons: meth- comb. form, -ene comb. form.

Etymology: < meth- comb. form + -ene comb. form, after German Methen (A. W. Hofmann 1866, in Monatsbericht der Königl. Preuss. Akad. der Wissenschaften zu Berlin, 1865 653).

Chemistry.

1. A divalent —CH₂— group; = methylene n. disused.

ΘΚΠ

the world > matter > chemistry > organic chemistry > hydrocarbons > [noun] > hydrocarbon radicals > named, by number of carbon atoms > one

methylene1835

methyl1840

methene1867

1867 A. W. Hofmann in Proc. Royal Soc. 1866–7 15 58 According to this principle the following names are formed:..Methane, (C H₄)⁰. Methyl, (C H₃)′. Methene, (C H₂)″. Methenyl, (C H)‴.

1881 H. E. Roscoe & C. Schorlemmer Treat. Chem. III. i. 266 The dyad radical methene.

1911 Science 1 Sept. 286/1 Yttrium methene disulphonate Y₂[CH₂(SO₂O)₂]₃ + 2½H₂O?

1922 J. J. Sudborough Bernthsen's Text-bk. Org. Chem. (new ed.) i. 50 Methylene (methene), CH₂, does not exist [independently].

2. The trivalent =CH— group; = methine n. Now chiefly Biochemistry.In quot. 1923, also a compound containing this radical.

ΚΠ

1923 Chem. Abstr. 17 3186 [The copper salt of] bis-[2,4-dimethylpyrryl]methene, C₂₆H₃₀N₄Cu (0.2g from 0.5g. of the methene), green needles.., shows..an absorption band at λ490–515.

1947 Adv. Enzymol. 7 320 The porphins are 16-membered-ring compounds containing four pyrrole rings bound together at their α-positions by ≡CH, methene, bridges.

1988 L. Stryer Biochem. (ed. 3) vii. 144 The four pyrroles are linked by methene bridges to form a tetrapyrrole ring.

2000 Jrnl. Biol. Chem. 275 6857/1 Large differences in spin lattice relaxation of the stearoyl and arachidonoyl methene and methyl groups were demonstrated.

This entry has been updated (OED Third Edition, December 2001; most recently modified version published online March 2022).

单词	methene
释义	methenen. Brit. /ˈmiːθiːn/, /ˈmɛθiːn/, U.S. /ˈmɛˌθin/ Origin: Formed within English, by compounding; modelled on a German lexical item. Etymons: meth- comb. form, -ene comb. form. Etymology: < meth- comb. form + -ene comb. form, after German Methen (A. W. Hofmann 1866, in Monatsbericht der Königl. Preuss. Akad. der Wissenschaften zu Berlin, 1865 653). Chemistry. 1. A divalent —CH₂— group; = methylene n. disused. ΘΚΠ the world > matter > chemistry > organic chemistry > hydrocarbons > [noun] > hydrocarbon radicals > named, by number of carbon atoms > one methylene1835 methyl1840 methene1867 1867 A. W. Hofmann in Proc. Royal Soc. 1866–7 15 58 According to this principle the following names are formed:..Methane, (C H₄)⁰. Methyl, (C H₃)′. Methene, (C H₂)″. Methenyl, (C H)‴. 1881 H. E. Roscoe & C. Schorlemmer Treat. Chem. III. i. 266 The dyad radical methene. 1911 Science 1 Sept. 286/1 Yttrium methene disulphonate Y₂[CH₂(SO₂O)₂]₃ + 2½H₂O? 1922 J. J. Sudborough Bernthsen's Text-bk. Org. Chem. (new ed.) i. 50 Methylene (methene), CH₂, does not exist [independently]. 2. The trivalent =CH— group; = methine n. Now chiefly Biochemistry.In quot. 1923, also a compound containing this radical. ΚΠ 1923 Chem. Abstr. 17 3186 [The copper salt of] bis-[2,4-dimethylpyrryl]methene, C₂₆H₃₀N₄Cu (0.2g from 0.5g. of the methene), green needles.., shows..an absorption band at λ490–515. 1947 Adv. Enzymol. 7 320 The porphins are 16-membered-ring compounds containing four pyrrole rings bound together at their α-positions by ≡CH, methene, bridges. 1988 L. Stryer Biochem. (ed. 3) vii. 144 The four pyrroles are linked by methene bridges to form a tetrapyrrole ring. 2000 Jrnl. Biol. Chem. 275 6857/1 Large differences in spin lattice relaxation of the stearoyl and arachidonoyl methene and methyl groups were demonstrated. This entry has been updated (OED Third Edition, December 2001; most recently modified version published online March 2022). < n.1867
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