瞬烯

瞬烯
	IUPAC名; Tricyclo[3.3.2.02,8]deca-3,6,9-triene; 三環[3.3.2.02,8]-3,6,9-癸三烯
英文名	Bullvalene
別名	Bullvalen
識別
CAS號	1005-51-2
PubChem	136796
ChemSpider	120549
SMILES	C\2=C\C/1\C=C/C3C(\C=C\1)C/23;
InChI	1/C10H10/c1-4-8-9-5-2-7(1)3-6-10(8)9/h1-10H;
InChIKey	UKFBVTJTKMSPMI-UHFFFAOYAK
性質
化學式	C10H10
摩爾質量	130.19 g·mol⁻¹
熔點	96 °C
沸點	400 °C分解
	若非註明，所有數據均出自標準狀態（25 ℃，100 kPa）下。

瞬烯（化學式：C₁₀H₁₀）是一個碳氫化合物。瞬烯是流變分子之一，其分子內所有的碳碳鍵不斷地發生Cope重排，從而存在多個價互變異構體。^[1]

瞬烯最早在1963年由G. Schröder通過光解環辛四烯二聚體而得，同時生成副產物苯。^[2]

高溫時，快速的分子內重排與結構對稱性，使瞬烯所有碳原子和氫原子在核磁共振實驗中呈現等價。重排可能產物多達10!/3 = 1,209,600個 (未計算對映異構體)，下圖僅列出其中的五個。

瞬烯在室溫下的質子NMR譜有一個寬峰，表明可以分辨出分子中不同的氫原子。在二硫化碳做為溶劑、溫度120.3 °C時，瞬烯的¹H NMR譜只存在4.237 ppm一個尖銳的吸收峰，說明分子重排速度大於¹H核磁共振的弛豫時間，無法被分辨出來。 ^[3] 變溫¹³C NMR實驗與變溫魔角固體核磁共振(¹³C CP-MS NMR)實驗中亦可觀察到快速的平衡反應。^[4] Martin由變溫核磁共振實驗得到瞬烯結構變化所需要的活化能為11.8 kcal/mol。^[5] Patel等人於2020年發表的研究工作中通過理論計算發現瞬烯衍生物的構型重排時所需要的活化能約為14 kcal/mol。^[6]

參考文獻

^ Ault, Addison. The Bullvalene Story. The Conception of Bullvalene, a Molecule That Has No Permanent Structure. Journal of Chemical Education. 2001-07, 78 (7): 924. doi:10.1021/ed078p924.
^ Schröder, Gerhard. Preparation and Properties of Tricyclo[3,3,2,04,6]deca-2,7,9-triene (Bullvalene). Angewandte Chemie International Edition in English. 1963-08, 2 (8): 481–482. doi:10.1002/anie.196304814.
^ Oth, Jean F. M.; Müllen, Klaus; Gilles, Jean-Marie; Schröder, Gerhard. Comparison of 13C‐ and 1H‐Magnetic Resonance Spectroscopy as Techniques for the Quantitative Investigation of Dynamic Processes. The cope rearrangement in bullvalene. Helvetica Chimica Acta. 1974-07-17, 57 (5): 1415–1433. doi:10.1002/hlca.19740570518.
^ Meier, B. H.; Earl, William L. Fluxional behavior in the solid state: bullvalene. Journal of the American Chemical Society. 1985-09, 107 (19): 5553–5555. doi:10.1021/ja00305a054.
^ Saunders, Martin. Measurement of the rate of rearrangement of bullvalene. Tetrahedron Letters. 1963-01, 4 (25): 1699–1702. doi:10.1016/S0040-4039(01)90897-4.
^ Patel, Harshal D.; Tran, Thanh-Huyen; Sumby, Christopher J.; Pašteka, Lukáš F.; Fallon, Thomas. Boronate Ester Bullvalenes. Journal of the American Chemical Society. 2020-02-11, 142 (8): 3680–3685. doi:10.1021/jacs.9b12930.

[1] Ault, Addison. The Bullvalene Story. The Conception of Bullvalene, a Molecule That Has No Permanent Structure. Journal of Chemical Education. 2001-07, 78 (7): 924. doi:10.1021/ed078p924.

[2] Schröder, Gerhard. Preparation and Properties of Tricyclo[3,3,2,04,6]deca-2,7,9-triene (Bullvalene). Angewandte Chemie International Edition in English. 1963-08, 2 (8): 481–482. doi:10.1002/anie.196304814.

[3] Oth, Jean F. M.; Müllen, Klaus; Gilles, Jean-Marie; Schröder, Gerhard. Comparison of 13C‐ and 1H‐Magnetic Resonance Spectroscopy as Techniques for the Quantitative Investigation of Dynamic Processes. The cope rearrangement in bullvalene. Helvetica Chimica Acta. 1974-07-17, 57 (5): 1415–1433. doi:10.1002/hlca.19740570518.

[4] Meier, B. H.; Earl, William L. Fluxional behavior in the solid state: bullvalene. Journal of the American Chemical Society. 1985-09, 107 (19): 5553–5555. doi:10.1021/ja00305a054.

[5] Saunders, Martin. Measurement of the rate of rearrangement of bullvalene. Tetrahedron Letters. 1963-01, 4 (25): 1699–1702. doi:10.1016/S0040-4039(01)90897-4.

[6] Patel, Harshal D.; Tran, Thanh-Huyen; Sumby, Christopher J.; Pašteka, Lukáš F.; Fallon, Thomas. Boronate Ester Bullvalenes. Journal of the American Chemical Society. 2020-02-11, 142 (8): 3680–3685. doi:10.1021/jacs.9b12930.

[1]

[2]

[3]

[4]

[5]

[6]